Don't trust software that claims to "shrink the drive no matter what, and move unmovable Windows files safely"!
If that were such an easy task, then why would you get "SuperDuper Shrinker 42" in the first place instead of using just any other tool?
If you're not going to switch to Win10 anyway, then you'll have to abandon Redmond at some point or another. So why not do it right now? The best way to learn swimming is to jump in at the deep end.
Oh, and start making regular backups! I know it's not a popular topic, but if you even have to think about rescuing your data from a borked system, then you need to rethink your backup strategy.