My system preferences for the trackpad keep changing randomly

So after my beloved 2011 mac died I was forced to acquire another one, so I got this new 2015 (the new 2017 ones are awful: hyper expensive, no storage space, huge trackpad and smaller keyboards, NO USB slots while everything else I have needs them, why...), that despite having a ridiculously limited storage space is slowly making me love it as I loved the other one.

Thing is that the system preferences situation is maddening... when I first had a problem with dragging files and things clicking themselves because the stupid "Tap to click" thing, I discovered for the first time that those options existed and lived in the Systems Preferences, in "Trackpad" and "Accessibility -> Mouse&Trackpad -> Trackpad Options" respectively, so I arranged things to my liking. The problem is that they keep changing by themselves! I wouldn't say that they are reseting to default because every time this happens, at random times, there are different options checked or unchecked, specially in the Trackpad, Accessibility does seems to default to the unchecked "Enable dragging" box.... is madening.

A solution to lock my preferences into place please?

Version El Capitan 10.11.6 doesn't show up in the options bellow, before you criticize me for not updating, I did try to update to High Sierra, but after like 6 trials I gave up, the installation windows gets stuck, says 2 hours but doesn't move, not even when I left it overnight.