graphics slowdown

i have a 1.8 ghz with 512 mb of ram, a radeon 7200 64mb ddr, and a 80Gb hard drive that has about 10Gb of space left. Theres another computer next to me that has half the ram and a geforce 2 with only 32mb of memory and probably a smaller hard drive with more free space. The lesser computer sometimes slows down but the other computer starts slowing down a lot when playing games and i can see the hard drive light coming on a lot and i've defragged the hard drive a bunch of times already. Anyone know of anything else i could try?

I also have norton's whole suite running in the background...do they slow things down?

LOL of course the whole suite will, there's your problem right there. You can look in the Task Manager, Processes, to see what's taking up the CPU time.

norton is evil

but a radeon 7200 is pretty bad.