thanks, I've downloaded a couple of things to stick on a usb stick and try.
If I remember rightly, boot into safe mode, restart and then boot from usb... something like that.
I'm fairly sure there's something in BIOS that does similar... been a while since I last saw anything like this, so may be wrong.
I've downloaded ophcrack live cd iso (which is going onto usb stick shortly) and one called 'UAC'. Both of which I've seen on noteable forums.
I just can't get my brain around anything complex at the moment and I want whichever bit of software works to be on a usb drive she can do herself if it happens again, provided I'm able to remember myself how I did it (or didn't!)
Just hoping this does the job... I shall report back when it's either a) fixed or b) I'm tearing my hair out.
Thanks