I have production Premium as well.
In XP:
Go to: Start > Control Panel > Add or Remove Programs > Adobe Creative Suite 4 Production Premium then click the Change/Remove button.
You’ll get the option to uninstall just Premiere Pro.
When you are done just use the install disks to reinstall just Premiere Pro. Make sure all of your other programs are closed and your Anti-virus software is off while installing.
-Larry