Switched on Pc, all looked fine but nothing responding.
Usually it's because it's doing an update- it didn't seem to be but I couldn't get the task manager. Then I did get it by right-clicking, but nothing was using any power

Re-booted, obviously...just the same.
Finally Bb said, what if it's the mouse? - we're clicking and getting nothing, but that right-click worked

Yep, as simple as that!
Except we plugged in the new mouse - which came with the new keyboard I bought not long ago, and decided to get the one with a mouse because of sod's law

