Thanks to NTCompatible who pointed out that Hewlett Packard have published a ton of drivers for Printers installed on Windows XP. So if you have a printer that won't install on XP take a look there you may find an updated driver for your printer.
An example of an XP driver is this:
Hewlett Packard have also started adding drivers to their pages for Windows XP, but based on the number of products they have, it will take a while I guess - LOL!
Download: XP Drivers on the FTP @ HP