If you're worried about a $100 camera just go to a nearby store and play with the display models and find one that feels nice.

As for tough or underwater I would forget these. Underwater goes 2x-3x the price for still mediocre pictures (note: most people do not discern between mediocre and good quality anyway, much more relevant to printing that posting on facebook). Your actual underwater usage will likely be very low, but I guess if you were in a pool or something it might be handy.