looking at my iMac on my sig am i able to run all games or just some basic ones? right now my wife runs diner dash 2 and ive loaded an age of empires 3 demo and they both run fine. If i get the full version of say COD 2 or Guitar hero, Battlefield 2142, Star Wars etc...am i able to run these? I dont know much about Graphics cards. also, anyone know any good game download sites. even demos. ive been searching for a Battlefield 2142 demo forever. Low on money for full versions right now.