Hi! I am in the same boat as you-- I need to lose some weight and am on day 3 of a bike I bought at a really good local shop. I am 5'4" and ended up on a Trek 7300 hybrid bike. I am comfortable on the bike, and that is what you'll need to find-- a bike on which you are comfortable. As stated before, the fit of the bike is important. Mine feels great, even though it will take some work to increase my time in the saddle. It's a rough road getting back into shape! I'm new at this, too. If you'd like to exchange e- mail addresses, do you want to compare notes each week? It would help me with motivation. Best of luck!