This is a really weird one (to me at least).
I have a number of USB ("thumb" or "pen") drives. They are Ridata, Peak and two Maxells.
I have a machine booting Windows 2000 (P4 2.26, 1Gb PC2700). It is at SP4 and fully patched.
If I insert any of the thumb drives they are recognised and work just fine. If I leave a Ridata or Peak drive connected and reboot it works just fine.
If I boot with either of the Maxell drives connected it gets as far as recognising the processor (before the health and memory test) then freezes.
If I remove the Maxell drive, it unfreezes and continues to boot as normal.
My wife also has a machine with Windows 2000 at the same status. It will boot perfectly normally with either of the Maxell drives attached.
Anyone come across anything like that?