Just ride all the bikes in your price range, and pick the one that feels the best! I don't know how much difference there is in componetry at that level, but the bike shops can advise you about that. Look for nice smooth shifting and braking. If you still can't decide, consider which bike shop has the best follow-up, like free adjustments, etc. Or which bike shop is the most helpful, for later when you need them. When all else fails, pick the prettiest one :-)

Nanci