cavuman1,
I suggest you make a bootable clone on an external drive. Doing that takes the guesswork out of which files to backup before you do the clean install AND you will have a disk to boot from if the clean install fails. I have only done this on a Mac, but it has saved my data while dealing with a couple of disk failures.
Here's a good place to start:
https://www.pcmag.com/feature/363387...e-a-hard-drive