You've got exactly the same setup as my brother, bar the blu ray drive.
His system is not far off mine when both are on stock settings. My DDR3 and SLI system eats benchmarks compared to his system. But gaming wise he can run at the same settings as me.
I don't know, but I'm guessing your Q6600 would be a B3 chip. Meaning that you won't be able to clock it that far. Personally I'd be happy with what you've already got.