Resetting Default Stylesheet/Options Inspector

Question

While trying to learn about the use of Stylesheets and use of the Options Inspector, I have managed via misguided bravado or accident to change the global options for the default stylesheet in a way that makes editing more difficult (ie when holding down mouse cursor to select a block of text it converts the text to light gray and a difficult to read font; the cursor no longer blinks in place so it is difficult to place edits).

How can one revert the Options Inspector to the original values used when the system is initially installed?

Sorry if this is a duplicate, but reading through related answers, I don't seem to see or perhaps understand how to do this.

Answer 1

After not getting an answer from the MSE community, I contacted WR, who provided me with the following link:

WR Response

I post the link here in the event others face a similar problem. Essentially, it involves deleting the contents of a number of directories that Mathematica builds upon reboot. One word of warning, be sure to save all your recently opened files and stylesheets as they will be gone upon restart.