So my last beast of a computer finally kicked the bucket and my techgeek little brother had a lovely new one built for me. I think it's just what I need to start working on larger, print size (joy!) files, but I really want to get everything set up to get the absolute most out of this.

Specs as follows,

Pentium 4 3ghz (with hyper threading, my little brother exclaims, what this means to me, I don't know)
1 gb ddr ram
Nvidia GeForce FX 5700LE
Two 80 gb hard drives

running windows xp pro

I haven't even put PS on here yet, just Painter (because I couldn't wait, I neeeeeded to use my tablet again). I've read here and there that making a separate partition for PS to use as a scratch disk will speed things up, so how much space should I allocate to something like that? And there isn't anything like that that I would need to do for Painter is there?

I have one drive chopped up with a bit of space for windows, a bit of space for programs, and a bit of space that will likely be left empty. The second drive is empty thus far, but that's where I intend to do my file storing, and I'd assume stick the scratch disk space. So, scratch disk info, and any helpful tips for setting things up for the best will make me very happy.