Can this computer play wow?Amd Athlon(tm) 64 x2 Dual Core Procssor 4200+ 2.20GHZ?

Yes because you've got a pretty fast mainstream graphics card. Upgrade RAM to 3GB or 4GB if your Windows 7 is 64bit and you should be able to play many other exciting 3D games. A lot of current games are more dependent on the graphics card.