I have tried many things related to this thread

http://ubuntuforums.org/showthread.php?t=1642568

without luck. I unwittingly changed the ownership of the entire /etc/ directory using

chown -R username /etc/

Now, when I try sudo commands in the terminal, I get

sudo: /etc/sudoers is owned by uid 1000, should be 0
sudo: no valid sudoers sources found, quitting

I rebooted into recovery mode and tried various combinations of the following commands:

chown -R root /etc
chown root:root /etc/sudoers

If I go in the directory using the GUI, I can change permissions in the folder that way to get different combinations but none of those work either.

I am new to posting in the forum, so I apologize if I screwed up any standard of posting. Any help is greatly appreciated.
chmod 0440 /etc/sudoers