You probably get a very general map at check in, but Disney has lots of road signs and plenty of places to turn around safely and go back(please dont' cross multiple lanes of traffic to get to an exit, just turn around when/where it is safe to do) if you miss the turn you wanted. Disney is an easy place to get around, after a day or two you will feel like a pro.
Some people prefer to drive to parks because they don't want to wait(up to 20min) for a bus or don't want to take the chance of having to stand etc. If you drive you will not wait on a bus, but you may need to take a parking lot tram. The MK is the exception to the rule since the parking for it is at the TTC, across the lake and you will still need a monorail or ferry to MK, if you use a Disney bus you get dropped of right at MK. If you are just going to a park, bus or car is very little difference in my opinion. If you are going resort to resort, no parks, definitely drive. When you add in multiple resorts and parks it might be easier to have your own car rather than figuring out transfers