That looks good. Raid 0 is two drives, striped, - which is great.

With your setup - you'll need Vista 64 bit or 1 gig ram will go to waste.

If you get vista 32 you can only address a grand total of 4 gigs ram - that includes the video card. That leaves you 3 gigs to play with. So you basically have 1 gig of ram that you can't use.

Since the OS and other apps probably use 1 gig - that's 2 gigs free for 5 copies of wow. That's not enough, since each copy uses a min of 500 - 700 megs.

If you get vista 64 bit you should be ok ram wise. Although I'd probably suggest 6 gigs if you can manage it.