Or, if you have access to a WinXP OEM install CD, just reinstall Windows using the CoA product key on the bottom of the laptop. You can download the correct drivers from Dell's support website using the service tag number on another sticker on the bottom.
Boot from the CD, reformat the hard drive to NTFS, and install away. You'll be back on the rig pretty quickly.
(I have the exact same laptop, by the way. Not a bad little rig for it's time.)