Okay, here's the cliffnotes:

-Created new user account
-Deleted the one I had before right after.
-If I try to use sudo, or run anything as a super user... it says my account doesn't have permission.
-I pressed, System, Administrator, Users & Groups and clicked the key icon. I enter in my password and it tells me "Authentication failed" so I can't change my account privelges through the GUI.
-I tried using the Live CD to edit that file, but it denies me permission to edit the sudoers file.

Think that's it... could really use some help. This is with Ubuntu 9.10.

load up the livecd... mount the / partition...go to that directory...eg: mkdir /mnt/ubuntu && mount /dev/sda1 /mnt/ubuntu && cd /mnt/ubuntu
then type in chroot /mnt/ubuntu /bin/bash
then passwd
(this will set a root password) remember what the password is...
then exit && cd && umount /mnt/ubuntu

reboot and you should be able to gain su privs and take care of your prob...see various sites on how to add a user to sudoers file

Edit: had to fix the /mnt/ubuntu