Can't log in to my account 11.10

Probably a bug because ubuntu 11.10 is in development release, report it.

At boot, select recovery (2nd line) and after choose option without graphic.
After seeing prompt at console, try to log and check error messages.
Then run command "startx" and check again error messages.
Perhaps your login script is corrupted.

Examining the .xsession-errors (and .xsession-errors.old) files in your home directory and the /var/log/Xorg.0.log (and /var/log/Xorg.0.log.old) files may also be helpful.

If your Oneiric installation is not fully updated (i.e., it's been more than a few hours since it's updated), I recommend updating to see if that fixes the problem. You can do this on the command-line, since you don't have a working graphical login as an administrative user. To do that, press Ctrl+Alt+F1, log in (don't worry that you don't see anything as you type in your password), then run:

sudo apt-get update
sudo apt-get upgrade
sudo apt-get dist-upgrade

Then reboot and see if the problem has gone away. If it has not gone away, then as eNry suggested, you should report a bug (if you are willing to do so).

Before reporting this or any other bugs in Ubuntu, please make sure to read https://help.ubuntu.com/community/ReportingBugs carefully. Usually you should report bugs with Apport (i.e., by running the ubuntu-bug or apport-cli utility), and this is definitely one of those cases.