I am in the market for buying a good bycicle.* I need one that will hold my weight. any suggestions?

A rugged mountain bike should work well, they are made to take jumps and ride on rough terrain, so you should have so problems with the strength of the frame. You should probably pay at least $250 - $400*(new)*for a decent bike, when you get cheaper than that you start running into really cheap materials. one way to save $ is to find a model you like, and look for it used.
-cd*

Depends on whether you want a mountain bike or a street bike.
They are very different.** Mountain bikes are more versatile - you can ride them anywhere.* Street bikes are easier to ride but you have to stay on smooth pavement.

Whatever you get - spend the extra money ($20-$40) for the "Gel Seat".* It's a seat that has some kind of hi-tech gel as the padding and is much more comfortable than the old style seats.

I have a Trek brand mountain bike and love it. I agree that you should probably get a gel seat though. Makes it so much more comfortable!!
*
--Heather

i dont know anything about bikes! But i wanted 2 wish you the best of luck on your weight loss journey!!!