Vista back to xp (by 2 users)

The best way is to simply format your hard disk drive (HDD) and re-install your XP software. Do you need instructions on how to do that, or did you expect there to be a simple shortcut with Vista? Unless you installed Vista onto a separate HDD, you're going to have to format the disk. Make sure you make back-up copies of any files you need to keep before you format, because after you do that it can't be un-done (at least not without a great deal of trouble, risking long hours of recovery and loss of most if not all of the files you're after).