I was looking into our resources to find something to help troubleshoot the issue you are seeing here.
I think the best article to use would be this one iTunes for Windows XP: Troubleshooting unexpected quits found here: http://support.apple.com/kb/ts1421.
While the name of the article is not what you are experiencing, the troubleshooting underneath is relevant.
Start iTunes in Safe Mode
Open iTunes in Safe Mode to isolate any interference with plug-ins or scripts not manufactured by Apple.
- Hold down the Shift and Control keys while opening iTunes. If performed correctly, you should see a dialog that says "iTunes is running in safe mode" before iTunes finishes starting up
- After clicking "Continue", determine whether the issue you were experiencing persists in Safe Mode.
If you see the same issue while iTunes is in Safe Mode, proceed to the Create a New User Account section below. If you do not experience the same issue, consult iTunes: Troubleshooting issues with third-party iTunes plug-ins for steps on how to remove third-party plug-ins.