This is just a heads up for anyone who has to install/reinstall/repair an XP installation on a PC which has a Belkin 4x4 USB peripheral switch installed.
The 4x4 switch is similar to a normal multiport USB switch, but it allows 4 computers to be connected to it - basically a way to network non-network peripherals (including printers etc) to multiple computers.

I've used one for a few months, and have had a few problems (some PCs would have problems trying to select devices) but I came across a problem last week which at first had me stumped.

I was creating a batch of cloned disks for my main PC (for security - multiple copies to be used as backups) and one of the clones failed, so I thought I'd see if a repair installation would fix things (I know the easiest thing was to re-clone, but I was experimenting!)
I put the XP cd in and rebooted, and when the system got to the first screen of the cd installation, it froze, and the dialogue bar (the bit where you get the 'installing x,y,z driver etc) at the bottom of the screen didn't appear. I initially thought it was a cd problem as the disk was a bit scratched.
I eventually traced it to the 4x4 switch - if it was removed from the system, the cd installation continued as normal; whilst if it was plugged in, the installation would hang.
I just thought that this info could save a few headaches - I assume that the installation is trying to configure basic USB support, but as this is a logically switched device, it falls on it's backside.