Welcome, Jude! I got on my bike again after quitting smoking and drinking, so I know the reward getting your life on a positive track can be! And you will grow to love being on the bicycle for more than just maintaining or losing weight. You'll find it is time for you to reflect, be by yourself, and see places you can't see in a car. Congratulations on your awesome decision.

I agree with the other posters. Start with a hybrid. Or even just buy a cheapo hybrid to get you going from Craigslist while you shop for a bike you will love. That way, you can ride down to the bike shop! Most important is a saddle that supports your sit bones and is not too too cushy because it actually can make a ride hurt worse if the seat is all foam. Don't worry about if you can remember to ride a bike. Just take it slow at first and enjoy it!