I don't think you'll have a problem.
I have a 4+ year old Pentium 4 2.8 ghz which is just single core. Dual core didn't even exist yet when I bought it.
2 gigs of RAM
2+ year old video card - Radeon x800 GTO 256 meg. Pretty low end nowadays.
And I run at 1440x900 on my widescreen monitor with everything set to at least high and a few to highest with no slowdowns other then in some really massive battles. Even then frames still stay above 20 so it's not too bad.
I do 3 simple things to do so well:
1) Turn off bloom
2) Turn off dust and debris
3) Turn off elevators
None of those enhance things all that much anyway.
So if you have anything better then my 4 and a half year old single core PC I think you'll be just fine on all high settings.