I would completely disable this resolution in the xorg.conf
Oh crap, now I can show off my command-line... skills
This should take you to the command line. Don't panic - the desktop is still on srg-alt-F7
to go to the directory /etc/X11/ type
Now comes the funny part. You need a command line editor. I always guess my way through them. vim or vi should be installed.
Somewhere at the end of the text file are the default resolution - There should be a section that sais "default depht" - most likely 24
You can eighter delete the monster resolutions from all dephts, or just go to the line that sais "your default depht" - in my case 24, and delete them, save, exit, reboot.
I'm going to edit this a little bit later on with a vi-walkthrough
After re-reading the first post, I see there probably is no need for a vi-walkthrough.