For your height. I wouldn't get anything lower than a 23 inch frame. Some places a 23 inch (58 cm) frame is the biggest they have in stock. If you ride on the streets and stay mostly off dirt roads, then a mountain bike would not be a good idea. Mountain bikes are mostly heavy and have large knobby tires. Which will be too slow and hard to pedal on concrete, cement etc.
You can always change the mountain bike's knobby tires to slick tires, but I rather get a bike that fits and will do what I need it to do. If you want a speedy bike. Get a road bike or a bike with 700c wheels (hybrids etc). If you want to stay mostly off roads, than get a mountain bike.
Last edited by ChowChow; 01-22-12 at 07:38 AM.