SawThe Light,
You must have Nero 5.5.5.1. or later in order to use it with WinXP. You could try booting in Safe Mode and see if you can uninstall Nero.
If you end up doing a clean install of WinXP on that computer again, try burning a CD with the Windows Burning Software, just to make sure there is not a problem with the drive.
Take Care,
Richard