Dude, don't freak. Go to
www.nomadness.net. Sounds like you don't have the proper updated drivers on XP. Checkout their download section for the Jukebox 3. Download all the latest appropriate drivers.
I tore my hair out too. Then, I went to the above site and everything works fine (Firewire and USB). Obviously, the Creative OEM software was not XP friendly at the time of its release. FYI, I have XP Home.
I'd headin' out soon to run errands and go to the Syracuse vs Hofstra game up at the Dome. If you need more help, PM me and I'll get back to you tomorrow.
Peace.