Types of races:
Circuit - This is one of the most typical types of races. You will have to complete a few laps (2-4 in most cases) in order to finish this challenge. Unlike most of the other races you won't have to be focused all the time. The most important is the last lap. It happens mostly because AI is cheating a lot. I was telling you this before. Nonetheless, I'd recommend spending earlier laps on exploration. You will have to memorize shortcuts and more difficult corners. You should also know when to expect some kind of attacks from the other drivers. If you're lucky, you probably won't have to repeat these challenges, because in most cases they're very simple.
Lap Knockout - Lap Knockouts are much harder. The rules of these type of challenges are very simple, though. At the end of each lap the last driver is being eliminated from the race. Unlike previously mentioned Circuits, you have to be focused all the time. Thankfully, most of the Lap Knockouts take place in known locations, so you don't have to memorize anything else. Remember to use shortcuts in order to extend the lead. This is very important, because if you make some kind of mistake you can't end up behind other cars.
Sprint - You should know these type of challenges very well. The objective is simple. You've got to be the first driver to reach the finish line. There aren't any laps. I have to inform you that most of the Sprint races aren't that long (3-4 minutes). You have to be focused all the time and especially while getting closer to the finish line, because the opponents may try taking away the lead from you there. You can't afford making any major mistakes. You will also have to use shortcuts along the way.
Drag - You will probably remember these types of races from the "NFS: Underground" series, however I must inform you that the rules have changed a little since the last time. In the previous games you had to concentrate most of your attention on gear changing or activating nitro. In "Most Wanted" you will have to deal with some thick traffic. Changing gears is less important. Furthermore, in some of the Drag races you won't even have to use Nitro! Instead, I'd recommend activating the Speedbreaker feature from time to time. Thanks to that, you should be able to avoid most of the vehicles, even while moving at higher speeds.
Speedtrap - This is a completely new type of challenge. It's connected to the presence of speed cameras. You should know them from some of the milestones challenges. The rules aren't that complicated as you might have probably suspected. You will have to score high speeds near visible checkpoints (speed cameras). You should probably know by now that you won't have to be the first driver to reach the finish line in order to win this type of challenge, however it won't hurt anyone to leave the other drivers behind. In the earlier stages of the Career speed cameras are located mostly near long stretches, however later in the game they will begin to appear in the middle of very difficult corners. You have to be ready for that.
Tollbooth - That's also a completely new type of challenge. Thankfully, you shouldn't be worried about it too much, because ALL of the Tollbooth challenges are VERY EASY. I'd recommend taking them down before taking down any other types of races. The objectives are rather obvious. You will have to reach a checkpoint within a designated time. Once you've done that the time limit is being exceeded. I must inform you than in most cases you should be able to finish these challenges much earlier than expected... that is, if you don't make any major mistakes along the way.
Police pursuits are consider to be one of the most important elements of "Most Wanted". Furthermore, there are many types of chases. Some of them are very easy, while the others will require you to do some incredible stunts. One of the key factors connected to this aspect of the game is level of a police pursuit. This element has some major influence on many other things. In most cases the pursuit starts on a first level. It means that you will be avoiding only a few of the slowest police vehicles. Furthermore, cops won't even try hitting you. Instead, they will only take part in a high speed chase. You don't have to worry about their actions at all. Even if you hit something along the way you will be able to get back to the main road without any problems. Furthermore, you should be able to outrun police vehicles quite easily. You might also consider hitting them. It's not that hard as you might have probably suspected. Damaged police vehicles will probably stop the pursuit. You will be informed by the level of their damages. You will only have to take a look at the intensity of the smoke coming from the engine. Furthermore, damaged squad cars are significantly slower.
Sadly, I must inform you that the first level of a pursuit doesn't last too long... mostly 15-30 seconds. Getting to a higher lever depends on a few things. If you want to advance quickly you should try taking risky manoeuvres, hitting other cars or damaging police vehicles. You will be informed about the current progress of the pursuit. As you might have probably suspected, advancing to a higher lever of a pursuit will only mean more trouble. Sadly, you can't stay on the first level, because you won't be able to accomplish any of the milestone challenges. Now for the changes... first of all, slow police vehicles will be replaced with much faster cars. Losing them will require some thinking. Furthermore, the police vehicles will try to ram you off the road. You have to avoid their attacks. Remember that you can only be caught when forced to a complete stop. Furthermore, you will have to stay that way for at least a couple of seconds. It mostly happens when you're being surrounded by a larger groups of squad cars. You will also be encountering some roadblocks along the way. This is a VERY important aspect of this game. You shouldn't be escaping from roadblocks by going the other way. Instead, you must break through them or avoid them (use the nearby grass). Roadblocks are being set only when moving at a straight line and staying on a road for at least a couple of seconds. You shouldn't be changing directions too often. Roadblocks can be "neutralized" in two different ways. The more obvious solution requires you to use the nearby grass in order to pass through safely. Sadly, in some cases it's not possible to do that, mostly while moving in narrow alleys. Like I've said many times before, you should stay close to freeways all the time. Remember that even if you're using the grass you will be able to score a point for a successful action. The second method will require you to break through a roadblock. It's very dangerous, although if you have a powerful car you shouldn't be caught by doing this. Remember to aim at the trunk of the vehicles, because their engines are much heavier. If hitting a roadblock stopped your vehicle change to reverse IMMEDIATELY, so you won't be blocked by any of the surrounding cars.
The third level of pursuit means only some mild changes. You will be encountering more roadblocks. Bear in mind that they will be heavier defended, so you've got to be very careful. Furthermore, police vehicles will be replaced with professional sports cars. Outrunning those may be a problem. The police forces will be trying to get you off the main road by using any means necessary. You should also know that you may be attacked by police SUV's. Unlike any other vehicles, they will appear in random locations. The police SUV's will be driving at very high speeds. Their main goal is to hit your car, so you HAVE TO avoid them at all costs. The best way to do that is to activate the Speedbreaker feature. Thanks to that, you should have enough time to plan your next movements. You should also know that SUV's may appear near some of the roadblocks. You should try avoiding them. DON'T even try breaking through them, because you won't be able to... even if you have a very powerful car.
The fourth level of a pursuit equals to SERIOUS trouble. The police forces will do their best to stop your vehicle. First of all, you will have to remember about the possibility of encountering spike strips. They will be replacing most of the usual roadblocks. The rules haven't changed since the last time, HOWEVER you will have to remember about some things while planning next movements. Having contact with one of the spikes will result in an immediate failure, mostly because your vehicle won't be able to move fast enough to outrun any of the police vehicles. I'd recommend using the Speedbreaker a lot. Thanks to that, you should be able to avoid these kinds of roadblocks without any major problems. DON'T even try hitting them, because you might end up near one of the spikes. Fourth level will also mean faster police vehicles and more SUV's. Remember that you will have to avoid them at all costs. Finally, you will have to deal with the presence of a police chopper. He will inform cops about your current movements. Thankfully, the chopper won't attack you in any way. Furthermore, you will be able to avoid it by hiding in one of the covered spots (hideouts, buildings...). Otherwise, you would have some serious problems losing it.
The fifth level is the highest one. The only exceptions include two final pursuits. One of them ends the Career mode. This time you will have to deal with Sergeant Cross and his men. Police officers are driving very powerful Chevy's. Outrunning these vehicles is almost impossible. You will have to destroy them or use the huge constructions to slow them down. You will also have to be VERY lucky at some points of the chase... Well, good luck then! ;-)
It would be a good idea to tell you more about other elements connected with the police pursuits. One of the most important things involves the presence of huge constructions on the map. You will have to use them to your advantage, mostly to lose the current pursuit. I have to warn you, though. They aren't that effective on higher pursuit levels. In that case, you shouldn't be concentrating all of your efforts on reaching these spots. Reinforcements are also very important. You've probably noticed that the game shows you how many police vehicles are taking part in the chase. Once you've eliminated most of them you WILL HAVE TO WAIT for the new cars. The game will present you with a correct time for the reinforcements to arrive. You can't lose the current pursuit, because new units wouldn't appear at that time. I'd personally recommend staying on freeways and concentrating on the drive itself. You should be able to maintain a pursuit without eliminating the rest of the police forces. In order to end the pursuit you will have to lose all police vehicles. You might want to head on to one of the nearest hideouts. They should be visible on your map once you've taken care of the chase. This is not necessary. You might look for some other areas, however there's a high probability of being spotted by the cops. I'd also recommend listening to the radio chatter. You will be informed about the current progress of the pursuit.