Wow, thanks everyone. Reser, I think our computers are expressing similar symptoms for different issues. My config folder wasn't nearly as big as yours. Also, I have an AMD graphics card, so I don't have any Nvidia drivers installed.
Turns out my windows folder is taking up 17.8 GB, and when I went through all the subfolders I found out that the biggest culprit was the WinSxS folder, which was taking up about 10 GB. Apparently that folder is supposed to get big, and there's not much to be done there.
Having done a more thorough search of all the folders, I've found out where most of the space has gone. However, there is still 9.2 GB unaccounted for, which is a much smaller issue than 30 GB, but still a significant chunk of my SSD space that I'd like have available.