Following this thread with interest . . .
Yesterday I took my old tower with Windows 7 into the local computer shop to have the Windows 10 upgrade. The shop was completely unable to make the computer connect to the internet so were not able to install the upgrade. There were bricking it that they had caused a problem. I took the PC home, plugged it in and, hey presto, Windows 7 fired up, internet connected fine and everything is hunky dory.
So now what do I do? I went to Curry's / PC World and they no longer do the Windows 10 upgrade. Interestingly the guy told me that Curry's own systems work on Windows 7 as they regard it as the more stable operating system. They suggested leaving Windows 7 in situ and installing McAfee Total Protection (£80 in Curry's but currently £16 on Amazon).
The caveat was to not use internet banking on the PC. That's fine with me so it looks like Curry's has the solution.
The alternative is to buy a new tower for several hundred pounds.
Comments welcome!