Firstly an apology to all who have helped and offered support and advice.
At the recommendation of my wife, after I became unable to respond to replies when the owner of the laptop I had been borrowing needed it back on Friday morning, I have had to cut my losses and get an engineer to "wipe" Windows and reinstall it for me.
You, and others elsewhere, have been of valued assistance to me, and now that my problems have gone I didn't want to leave this thread hanging. Thank you!