I tried System File Checker & the theme became available. But I would still like to know where such things are located. In the meantime, I will modify & save it so I can backup & store the settings.

I have a disk that messes up, so I do semi-regular chkdsk runs.
I now have Windows XP theme, but on the Display Properties, Appearance tab, the "Windows and buttons" pull-down window only lets me choose "Windows Classic style" -- "Windows XP style" is not available. The green Start button is gone [a 'windows' icon shows up], colors won't set, etc.
All this forces me to look at the old, boxy, windows 95 screen.

Does anyone know what file & location I can copy to get me the standard XP settings? I don't want to completely re-load. I DID try a restore point to a couple days ago, but that didn't help [didn't expect it to, but tried anyway]
BTW - I also had WORD crash; as it tried to open, it would error & ask me to send a report. But no matter what I chose, it would try to open again in a non-stop loop. A re-load OVER the existing installation did not fix it - had to uninstall WORD [I took out all of Office] & install anew. I don't want to do this for the OS.
Thanks