Geforce 9600 GT
Intel Quad-Core, 2.4Ghz.
3G RAM

For extra information, I can run Metro 2033 at med-high, with around 4x AA, and both games have the same system requirements. I'm also running it at 1600x900 resolution.

It will run. By comparison, I've a Radeon HD5770/Core i3 550@3.2Ghz/4GB RAM, and I can pretty much max the game out.

Medium wouldn't be a completely unreasonable expectation, but make sure your graphics drivers are up to date!

yea, shouldn't be a problem

Thanks Duders!
@Beyond_the_infinite: 
Btw, that site in my experience is pretty bad. half the time it doesn't know what to tell you, and in another third it's straight up wrong.

You should be fine.

Witcher 2 is remarkably well optimised to look nice for even 4-5 year old computer setups. So don't worry about it, it will, under most normal circumstances, still look nice and run well on your setup.