It is more important to find a good shop than to find the right brand of bike. All makes of bikes in the same price range will be similarly equipped. Since part of your aim is to lose weight, I assume you may be overweight. In that case it may be advisible for you to get the bike shop to fit you bike with stronger wheels (deep V, double wall, 36 spokes), and check that they are properly tensioned and stress relieved. Good luck.