if you have the XP installed,you have to use a third party program like partition magic which is risky but easy to use or you can uninstall XP/fdisk the HD and make a partition for XP but using fdisk needs more experience.
BTW do you mean seperate HD(dirve) or seperate partition?
I get in from work at 2 a.m. and sit down with beer
Turn on late night TV and then wonder why I'm here
It's meaningless and trivial and it washes over me
And once again I wonder is this all there is for me