If you've upgraded to Ubuntu 12.10 and you're getting an error message at boot that reads:
GSettings Data Conversion has closed unexpectedly
The problem seems to be related to the onboard keyboard. Uninstalling the onboard package should resolve the issue (assuming that you neither want nor need your onboard keyboard!).
sudo apt-get remove onboard
For information, see Ubuntu Bug #1047859.
I've actually given up trying to get 12.1 working: I'll wait until Canonical decides how it wants to manage virtual files.
Sources & References:
- Launchpad Bugs - Bug #1047859