First, everyone is right. A bit of anti-fog spray will do the trick. However, I may suggest sport goggles (lenses that are made to your perscription) and grip your face.
http://img.photobucket.com/albums/v427/ruthlessp8ntballer/blue_lens.jpg
spend extra cash on new glasses only for paintball. Just another option though. Oh yeah, my pair of Flex-7's worked fine for me with my glasses. Fans do suck, noisy, and break easily. Last time I checked, its okay to wear the glasses under your goggles. Hope this wasnt too repetetive, and helped a bit. Oh yes, save up for the lasik, thats what Im doing
Otherwise, stick to your glasses. Just slap some anti-fog on them, and they should serve you just fine. For Some Reason, The picture will not come up, and Im sure I did it right. The mods must have put a lock so you cant use pictures in this thread. Haha. Hope that helps.