OK, I did a bunch of sh*t and now I can at least open a terminal in Guest and then log in as myself. I went in there and re-installed nvidia-current. I thought then maybe I could get to a GUI, but startx just brought up a blank black screen, first with a cursor, then nothing. CTRL+ALT=f1 back to terminal gave me a repeating:
That repeated for several hundred lines, then
NO PROTOCOL SPECIFIED
xinit giving up
xinit unable to connect to xserver
I tried removing .Xauthority because that's what everyone always says to do. Updated and tried startx again. Black screen again. Back in terminal, it appears to be stuck on
xinit: server error
xauth: timout in locking authority file /home/anna/.Xauthority
Loading extension for GLX
ETA: Progress, I think! I did these steps to clean it up, and then I was able to log in normally but got an error that there were no settings for my monitor, or words to that effect. Purging Nvidia... again.
ETA: OK. I'm up and running. I have huge distorted graphics but it's working. Going to work on backing up my files in case I have to reinstall but I REALLY don't want to! Please tell me what to run to see what the deal is.