I'd scan the HDD (links to follow) for file system errors and malware to start. After that we can get a Web Speccy report for members to pick on. Here are the links:
1. CHKDSK /F /R /X (will run for hours so do this when you have the time.)
https://www.tekrevue.com/tip/fix-hard-drives-chkdsk-windows-10/
2. Malware scan by Grif. Read
http://www.cnet.com/forums/discussions/how-to-remove-pup-option-603542/#post-f742c795-5881-433b-a29b-6d758efe5cd3
3. Web Speccy report for here. Read how at
https://www.piriform.com/docs/speccy/using-speccy/publishing-a-speccy-profile-to-the-web
All the above is to avoid a nuclear option of a reset. Be sure your backups are current regardless of what you decide.
About 6 months ago my HP computer developed a strange problem. I have a blank screensaver set to come on after 15 minutes of idle time. Before, I would wiggle the mouse and then click the Google Chrome icon and i was off and running instantly. No waiting. Now it takes 3 to 4 minutes for anything on my computer to start. You can't surf the web or open anything! You can't even open the start menu. I went and turned everything to "never". Even the monitor has setting that I set to never. Doesn't matter what I do it won't work correctly. I even experimented and turned off screensaver and that didn't change a thing. I am essentially froze out of my computer every time I leave it and come back. I forget to add that any browser does the same thing.

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