How to make minimise-restore-down-and-X buttons permanently normal?

Many years ago, I installed a Mac OS X theme that changed the size of the minimise-restore-down-and-X buttons. When I decided to stop using that theme (also many years ago), I had to redownload Windows Explorer's explorer.exe file amongst other things, because that theme had required me to use a modified version.

Now, many years later, my computer is fine, other than the fact that the minimise-restore-down-and-X buttons are grotesquely large. I tried lowering their size number through the personalisation settings one can find within the Control Panel, but after shutting down the computer a couple of times or so, they reverted back to the grotesque-looking size.

Is there a way to fix this permanently? I'd rather not have them be an eyesore any longer.

RoWin7 said:

right-click desktop>personalization (it's actually the control Panel)>Window Color>drop down the menu> caption buttons. Fool around with it till the size is right. You can also control the old XP options there--size and color of menus etc.

I'll do it again, but like I said, I already did that. What ended up happening was that after two restarts, it went back to how it was.

I'm trying to figure out how to permanently fix this problem. Would a registry edit work?