Skyrim upgrade question

Depends on what resolution you're gonna be playing at, but i would say your computer will be able to handle Skyrim on medium settings at 1600x900 resolution  

Thanks, I only have a 1440x900 monitor... So maybe that's good enough. Think a moderately upgraded video card would get me smooth performance on high?

Well i play Skyrim at 1920x1080 with a GTS 450 on high settings with 40fps+ so i should say with the GPU you have now you will be able to play on high at that resolution   though i'm just speculating here   also my cpu and ram is not as powerful as yours i think   if you have the cash upgrading your video card would probs be a good idea, something like a Nvidia 560 Ti or a ATI HD 5850