Same laptop always slower after a few months with the same game?

I have the problem that I was able to play Game X 6 months ago without any problems, if I start it hacking and jerky it is the same with other games, only when I completely renew Windows it works again, I already have O&O Defrag & Optimization Programs… Used without success, but slowly getting annoying to secure everything every few months. What other software solutions are there?

There's no need for programs.

It is probably enough if you simply uninstall all programs that you do not need, or at least stop them if you want to play the game.

I have the problem that the disk usage is 80-95% as soon as I start the game / games. Before that, it worked well, why is that?

The hard disk or the hard disk controller may have a crack. However, only the driver for the controller can have a crack.

I just tested it again in window mode to see what was still working, as soon as it hacked, the data carrier went to 2-3%, but the CPU went to 100%. What can that be?

This is more normal behavior.

Only: so without information you can't expect any really useful answers.