[quote name='Wolve11']frosty, you recommend i just delete Vista and put XP on?
I'd like to have both and I have 2 external 500 GBs as well as 1TB internal so I know I have the room for both, but I have absolutely no experience messing around with OS, let alone multiple at once.[/QUOTE]
just saw this...

ing with the standard WinXP boot loader isn't bad, I don't think, but my experience is limited... i'm used to setting up linux on a machine already imaged with windows and then configuring grub or lilo to do the boot loading.
but if your pc gives you the standard boot dialogue before kicking into loading windows, you might be able to tweak it -- you'd just have to do the following:
(1) run the install for windows xp -- either have a new partition ready created or hope you can do it in the install mechanism ... in linux i'm used to it -- in windows, i'm usually used to destroying all partitions -- you may want to acquire partition magic and make the partitions prior to install.
(2) the install may add the correct shit to the boot loader... if it doesn't, well, i'd get back to you (i'm going to look now), but you'd find the best way to edit the bootloader from vista/xp and add an entry for the missing OS.
Edit: here's the MS how-to on getting it done if it's not done for you when you do the second OS install:
http://support.microsoft.com/kb/289022
If you have problems figuring that out, I'm sure I can help, just let me know.
(3) so long as you're dealing with straight windows, you should be able to use any file system type on the external drives and be aces... the problem occurs if you're using storage like that in linux, or on the PS3, or something, as other OSes don't like NTSC, so FAT32 is your common denominator in terms of file systems.