If you're gonna game, go for the 9600, the 5200 is rubbish (believe me, I know, I have one in this Insipron 5150), the CPU speed won't make too much difference.
What screen size/resolution do you have, as for me, I'd get the highest resolution I could possibly get (this screen is 1600x1200 on a 15" panel, and I love it)
Confused