I found through a Google search a small app called Advanced System Font Changer, which I ran and it worked perfectly. It not only changed the desktop and File Explorer fonts, but also applied the change to things like the font in the Newsbar, all the Windows title bars, the tabs, bookmark bar, and URLs in Chrome, and I'm sure other things, and the changes stick- minimizing Newsbar has no effect any more. It requires no installation, and is very simple to use. It also allows resizing of the fonts and font effects, and control of things like icon sizes and spacing. It's an exe file so I can't attach it.