After upgrading to w10 my computer is a boat anchor

I have a laptop (Toshiba) and a desktop (HP). I upgraded to W10 on my laptop and had no problems for a couple days and then a overnight forced update made some of the new functions not work anymore. I used GeekstoGo to clear up some other issues and the lost w10 functions returned. Weird. I resisted upgrading to W10 on my Desktop until around Dec 2015. I responded to a post asking if I wanted to load W10. I thought it was time so I started the process. I just let it go and went about my day. When I came back to check on the progress, I discovered a black screen. I pressed and held the power button and started the computer again. There were none of the usual whirs and clicks. The computer fan came on and that was it. The screen was black. I repeated the process several times with the same results. I went south for the winter and when I returned I turned the computer on and lo and behold it booted up and apparently started working on the W10 upgrade again. I watched it finish and the screen was just like before the upgrade. Great. I let it run like I always do and the next day the screen was black again and it won't start, just like last winter. Any thoughts.