lol doublepost, but i have more info, and i need a bump
I have booted to safe mode after the repair install, and everything seems normal enough. This is an improvement! Sadly, I cannot repair or uninstall Office from within safe mode. I have tried both booting with the Office CD in and out to fix the install error, but there's no difference between them.
I'm gonna try to make another user account, to see if its linked to just that
EDIT: This is even weirder: windows is acting normally again
just randomly. meh