Fortunately Modern Warfare 2 does not need a high-end system to achieve playable framerates and your rig seems above average at least. MW2 and MW1 is quite similar in this matter, I believe they use the same graphics engine (of course MW2 has improvements over its predecessor)

If you want some hands-on experience, I have played MW1 with my old, crappy machine that has an Athlon XP 3000+, 1.5 GB DDR400 Ram and a Geforce 6800 GT. Yes, not even dual core and with a really old GPU, I managed to get around 40 fps in average settings at 1280x1024. Your rig is much better than mine so I don't think you'll have a problem playing it with high settings since it has good optimization (one of the best features that of MW has)in my opinion).

Of course, it will be down to your personal preference, resolution and etc. but you won't have to cut down the graphics too much.

Fortunately Modern Warfare 2 does not need a high-end system to achieve playable framerates and your rig seems above average at least. MW2 and MW1 is quite similar in this matter, I believe they use the same graphics engine (of course MW2 has improvements over its predecessor)

If you want some hands-on experience, I have played MW1 with my old, crappy machine that has an Athlon XP 3000+, 1.5 GB DDR400 Ram and a Geforce 6800 GT. Yes, not even dual core and with a really old GPU, I managed to get around 40 fps in average settings at 1280x1024. Your rig is much better than mine so I don't think you'll have a problem playing it with high settings since it has good optimization (one of the best features that MW has).

Of course, it will be down to your personal preference, resolution and etc. but you won't have to cut down the graphics too much.