That it would be Windows XP's Service Pack 2 that would give me trouble ...
But no .. once I took a better look it ws my A4 Tech brand new, Microsoft given on Windows Update site that did it .. I couldn't boot the blasted thing ...
Seems that it activates a service that makes it go "a bit" mad...
Off to the Windows text mode recovery console (always get it installed, very handy ... :) ), disable the service, remove the mouse on Windows, and install the old driver that came on the good old floppy disk :)
Magic.. Who says old things aren't good ? ;) eheh
Service pack 2 on the other hand is working fine so far... just my luck?