Try these steps listed below.
1. Run “c:\WINDOWS\system32\devmgmt.msc” (i.e. *Device Manager*), and leave it open for now for later use
2. Start up iTunes
3. Next, connect your iPod.
4. Go to your iPod Settings and select the “Enable disk use” option from under theSummary tab.
5. A dialog box will pop up reminding you that you’ll need to manually eject. Go ahead and hit OK
6. Hit Apply to save changes to the iPod
7. Quickly switch to the Device Manager window and right-click on any item within the window and select “Scan for hardware changes”
8. Finally, switch back to iTunes, and try re-syncing your iPod to see if it helped.
It might not also hurt to trash your iPod's Photo cache if it has one (i.e. you sync photos to the iPod). See this article for information on where to find this folder on your Windows XP machine.