Hey would you look at that, I've commented on that one
I would suggest the Radeon 5570 or 6570 with that power supply. I've had a Radeon 6670 on a 220W before, but I wouldn't say I recommend it at all.
If you were to get that Radeon 6570, they usually come with the driver on a disk in the box, but its usually an older version. The newest versions can be found on the AMD website. It would do well in all Source and stuff, but Skyrim might struggle.