you can't go wrong with Honda, they make everything to last. I'd stay away from Suzuki at this point. yamaha makes a good bike. Dirtbikes come in two flavors, 2 stroke and 4 stroke. 2 strokes require you to mix your gas with oil due to their funky oiling system and the engines have to be rebuilt more often. 4 strokes use regular pump gas and don't have to be rebuilt quite as often.
two strokes build lots more power the higher you rev them and can be scary to someone who's never ridden one before. 4 strokes tend to be more predictable have more torque and handle hard surfaces better.
Most manufacturers make two types of bike, recreational and performance. usually the performance run sizes 125, 250, 500, etc. all the other sizes are usually the recreational ones. Not to say that a racer can't be used for fun. Don't be intimidated by big displacement. My first motorcycle was a 1200cc, but it's a streetbike. A nice 250 or 400 4 stroke would probably be great as long as your careful. if you want a 2 stroker, go with a 125 or 250.
that's just my opinion, if anybody has any better info, jump right in.
Eric
