The system has been untouched physically since December and has been running without an issue.

Only updates to SageTV have been applied.

Right now I'm back with the Windows setup... And again I notice that I can't move the mouse pointer, so I know I'm going to be screwed when it asks me to click on something...

EDIT: OK, at least the PS2 keyboard/mouse work.

This time no IRQL error when installing devices. I'm now at the Regional/Language prompt. I'm going to see if I can finish this and then I'll do a repair again and try WITH ACPI...