I can totally relate, I wear glasses as well.. As far as the parks, I have been on Space Mountain, Splash Mountain, EE, Test Track, etc. with my glasses on and have not had any issues. My only recommendation would be to make sure that your glasses are completely on your face and pressed against your nose before the ride launches, I always do this especially on Space Mountain and EE lol.. If your glasses are loose and need adjusting I would recommend that you do this BEFORE you visit WDW just to be on the safe side..
As far as the water parks, I would NOT recommend wearing glasses on water rides, IMHO as a glasses wearer that cannot see without them this is actually one of the reasons why I avoid water parks altogether, I would rather avoid the hassle and prefer the main theme parks anyways.. If you must I would recommend either taking them off, or prescription sunglasses/googles as recommended by previous DISers.