Don, I've had so many problems with Windows 10 that I copied all my photos, all my documents and them dumped windows 10. I re-installed windows 8.1 and have had zero problems since. I also have anti virus programs installed plus Advance System Care Pro. My Linux computer never has any of these Windows problems!
To answer your question, if you have a licensed version of W-10, yes you can re-install it, but if you don't clean the virus out of the computer, chances are it will still be in there somewhere. When I took W-10 out of mine, I saved what I wanted to an external HD and then formatted the SSHD before installing 8.1. I have no problem with 8.1, some don't like it, but W-10 takes over the computer and is too controlling for me, I definitely don't like it! PJ
Forgot to mention, have you tried AVAST free anti-virus, it's a nice program and works well.