Select text suddenly boldened

All the text (excluding that of the menustrip and its items, and the window's title) in the Task Manager is boldened. The text in the Find and Replace box of Microsoft Word 2007 is also boldened, excluding the window's title. My other programs, and the rest of the computer's text, seems OK.

I attempted to adjust some of the fonts for Windows in the Windows Appearances window's drop-down lists; I changed them to Tahoma, but I only boldened more text, so I changed them all back to defaults--Segoe UI.

I had recently uninstalled various programs, so I assume one took with them some font files ...

When you are at the font selection menu there will be some buttons next to it make sure that the bold is ot pressed in.

They are not.

Then make them bold and apply the settings now un-bold them they might be back...
Otherwise check if you are changing the desired fonts and not something other.

Have you tried a System Restore, to just before you uninstalled those programs you mentioned.