^ He's right. You'll need to upgrade your GPU (Graphics Card). You have enough RAM/Memory, and your processor makes the cut also. Even if you upgrade your graphics card, your processor might make things a little rough.
Hi can i run MW2 on my pc?
SPECS: Windows Vista Home Premium
Processor: Intel(r) Core(TM) 2 Duo CPU E&200 @ 2.53 GHz 2.53GHz
Memory (RAM) : 4,00 GB
Graphics Card : NVIDIA GeForce 7100/NVIDIA nForce 630i
Yeah, the Geforce 7100 is actually an IGP... and not even a new one. Any sort of dedicated card would be an improvement (or practically any card- to be more specific, any PCI express card). With your current IGP, you can't play anything. However, for $70 you can pick up a Radeon HD 6670, which can draw all its power from the PCI Express slot (assuming you have one), and will provide entry level gaming options.
mw 2 and 3 have same graphics and requirements pretty much. Your cpu and ram are guaranteed to get 60 fps, but video card needs to be upgraded. No need for fancy things. get a new radeon hd 7770 or nvidia gtx460. They are dirt cheap. Or you can get my video card used