So far it seems ok. I can now fully rebind Controls to my likings. Of course my problem was subjective, so this might be an issue with different solution for other people in the future.

Oh wonderful, it was the NPClient. Who would've thought it could be something like this. Thank you very much for your time and advice. :)

I've uploaded the last one. As for the defragging, no I haven't done that in a while. And yes, I did reinstall Windows and everything on Disk C, but as for Steam games, they're all running fine as they were. Plus I had the issue even on my old PC, but the game didn't run well enough for me to play it, so I didn't worry about it much.