I recently found that my XP machine would never finish it's initial contact with my Jukebox recorder. It was working forever. I think it couldn't get past some failed seeks on the hard drive or something. However, a Windows 2000 machine could access it, if it was plugged in at boot time. (It also had trouble with first access if I just plugged it in once it was booted up)
I ended up using the 2000 machine to reformat the drive on the Jukebox, and then my XP machine could see it again. Although the XP machine is still slow, since it insists on "autoplaying" the drive when I plug it in. So it tries to search the entire contents, which takes some time.
My jukebox was very full, and without reformatting, I couldn't run chkdisk on it from the 2000 machine. Now I plan to leave a couple of Gigs free at all times.