So, after spending countless hours fruitlessly trying to resolve this problem, I decided to format my disc and reinstall XP.
After some adventures I managed to do this only to find that it was still crashing. I then took out one of the memory sticks and it stopped crashing instantly.
Such is life. Mr Gates kept insisting that there was a driver problem. My fault for not thinking about the memory at the very beginning (aka "the bleeding obvious").
I'm trying to reinstall Office and the other stuff. Hopefully (fingers and toes) I will be able to re-install my XP "back-up".
I suppose that I should on one level be really pleased with myself. Despite such extreme provocation I did not actually smash the computer to pieces with a hammer. It was (and still is) close at times. Thank God also, we have gun control in this country!
When Bill, when, will computers become as reliable as modern day cars and tellies?