In BF2 I can pull an average of 60fps (40fps min) at 1024x768, but that's with everything at low, dynamic light and shadows off. It also sometimes puts me at a disadvantage because the grass is more like a big blob instead of fine blades and is harder to see through. In FEAR, with video on medium, my frame rates sometimes dip down to 19fps, which is typically when there are two or three other people trying to kill me (successfully) and I need the fast response the most. I'd pony up a bit more for a 7600GT or a x1650xt if you want to play today's games and enjoy them more.
In Doom3 or RTCW I can run 1280x1024 with everything pretty much on high no problem, so for your games two years old or more it does work great.