Build your own.
Ram: 4gb. (I like kingston or crucial)
Proc: latest intel duo or comparable amd (not done my research here as I still have a pent 4 3.0ghz, but it still works fine, and I do vid editing and lots of 3d work)
Mobo: spend money on it, don't get the bargain here, get the nicest chipset you can. Your processor and ram are limited by your chipset, as is upgradability. (I like intel boards and asus.)
Hard Drives: Get whatever the best deal is for gb/$ in terms of hard drives, but I would agree you'd want a boot/os drive, and 2 sets of disks, one for source and one for target. (I like WD and Seagate drives, I would advise against using Maxtor, I've seen a lot of those die)
Currently I have 3 storage drives (all WD), and they are NOT set up in raid, but I do a fair amount of rendering back and forth between them, and they're fine. Raid just saves you in case one of the drives decides to die. I keep my 3rd drive for backup of project directories.
Video: Don't spend a fortune here, a decent gaming card will work fine. I have a Radeon 9800 128mb (256bit), and I use 3dsmax all the time. Still works fine. Unless you're gonna be doing high end 3d and painting a bunch of insane stuff in zbrush, you don't need a Quatro (although they're nice :Q)
The key here is to build a solid machine for under 2000$ and not spend what you don't have to. Don't think you need the latest hardware to get the job done, or that it's gonna be THAT much faster. You can use the rest of the money for software, or a camera, or other gear you might need. Always buy right under the curve of the newest hardware, so you get the most power/best deal for your money.
and... DON'T RUN VISTA.
my .02$
