Pop, as you know I went through this already (still going through it). Windows 10 was NOT the problem I had. I was nailed by a spam bombradment that had nothing to do with W10 installing itself. What was downloading itself was a legitimate copy of W10. W10 is seemingly an improvement over W8. That said, Microsoft is a-holes for trying to force it down our throats. Takes a lot of balls! You can do a CTL-ALT-DEL and bring up your task manager and kill the download by hitting the "End task" button. But bottom line is this W10 install that it is attempting to do will not screw up your computer. I raise this only because I posted that I thought it screwed me over when, in fact, this was not the case.
Beyond this, it's entirely up to you if you want to take Ret's advice and transition to Linux. I may do it at some point myself but not quite ready to pull the trigger.
Hopefully by Saturday.
