For the same or less you could also go with an 8800GT which is comparing a high end model to a low to mid range one. The 8600GTs and 9600GTs are each the lower end models in each series while the 8800s and 9800s are at the high end.
The 9600GT is simply another low end model in the newer series while the thing to look at when selecting a card for gaming is thing like support for antiliasing, antisostropics, etc. for visual quality as well as overall performance. Get a better performing card along with a better edition of Windows at the same time would be the thought there.