For the last several days, I have been wanting to nuy stuff from iTunes.

   Instead, I get this message:

   "iTunes has STOPPED working. A problem has caused the program to stop working correctly. Windows will close the program and notify you if a solution is available."

   I emailed Apple about it, but that wasn't the answer.  I uninstalled - and reinstalled - the latest version, and it's the same old, same old.

   I am using A Win10 Gateway SX2185.

   Does anyone have  a solution for a Win10 PC?

   BrianThis is not a direct answer. You can try alternatives to iTunes. Many work very well.
http://www.makeuseof.com/tag/alternatives-itunes-5-best-free-music-players-mac-os-x/
It SEEMS that Apple is not  doing all they can to maintain the cross PLATFORM users of their once great product. It is unlikely they will make efforts to support Windows 10. However, you can judge for your self.
https://support.apple.com/en-us/HT201668
Quote

If you can’t install iTunes on your Windows PC, or if you see “error 2” or "Apple Application Support was not found" after you install the software, follow the steps below ...

   I uninstalled iTunes and Quick Time, then reinstalled it and it won't work.
 
   I'm getting frustrated over this.