I can open eclipse,photoshop, COD Black ops with no fps lag and anything i have opened without any problem with my so old pc (Intel core 2 quad CPU Q6600 @ 2.40 GHz (Without overclock, i will burn it up with the current cooling system xD) and 2 GB Ram on windows 7 x64)
You can find very good specs with your needs, though you have to choose a good graphics card for gaming
Im using Ge Force GTS 250 , bought it just for cod at august