This problem started after upgrading from Ubuntu 12.04 to 12.10. I just used the upgrade option from the
Update Manager. Once, there was a connection failure. And it quit, but told me that all downloaded packages have been kept. Then a while later, after connection resumed, I started again. It all got over, and it finished upgrading, and then it said "Restarting the computer". Then it went into the Ubuntu restart/start-load screen and hung there forever.
I powered off the laptop, and restarted the laptop. Then after the start screen, the login screen loaded, which was sort of in a stretched 800x600 res. I log in, and I don't see anything at all except the wallpaper. No other component of the interface has loaded.
Need a fix or a safe way out. I don't even mind rolling back to
12.04 with just all my files intact.