Jmac, you da' man. That was cool of you to dig up his HP drivers site for him. I just took a gander and couldn't find chipset or USB drivers for that model:
http://h10025.www1.hp.com/ewfrf/wc/softwareList?lc=en&lang=en&cc=us&y=0&x=0&dlc=en&product=77567&os=228
, but I had a thought. Perhaps installing XP SP2 (if it's not already installed) would do the trick, since it's all but a full install of XP.
Alpine, you can get SP2 from the WindowsUpdate link Jmac provided, or find out there if it's not already installed. Preferably, you'll select the "custom" button, instead of the "Express" button, which will show you in the far left pane, all software, hardware, and critical updates available (instead of just the Critical ones that the Express option provides). You may have to run windows update multiple times (possibly with reboots between them, if you're prompted) until you get all zeros next to any available updates in the left pane.
However, not to be a skunk in the mud, but I haven't seen a USB driver issue solved by the provided driver updates on Windows Update. Hopefully SP2 or something else there helps you out. It may not hurt to also go into your Device Manager, "uninstall" the USB devices, then "scan for new hardware" and if it finds something, asking you for the install disk, point it to your restore or XP CD and see if you can get those INF's installed properly.