Ubuntu :: Somehow Lost Ability To Gain Admin Rights

I am semi new to linux and i was getting the hang of it until just recently. I'm trying to do some web design using php and mysql. In my reference material (the all in one desktop reference {for dummies}). At some point I needed to do something in /var/www but I ran into a permissions problem so I typed:
Code:
chgrp -v -r guy0203 /var/www
405 chgrp -v -R guy0203 /var/www
406 chown -v -R guy0203 /var/www

Afterwards in some subsequent step it suggested putting the files in /usr/src/mysql. Since I didn't have that folder I used mkdir and created it. Then I tried adding the files I needed to that folder and got denied on the grounds of not having permissions once again. So tried something like this:
Code:
451 chmod 777 /usr/
452 sudochmod 777 /usr/
453 sudo chmod 777 /usr/

It was a 755 originally but I couldn't copy those commands. It turns out as that I had two terminals open in different desktops. one of them was a root terminal. It was at this point that realized that I was in that root terminal and decided I was done 'learning' for the day. I decided to listen to some music (which is located in my windows partion) and ran into a problem. The prompt that pops up to normally asks me for my admin PW to mount the drive. Now just vibrates like an incorrect entry was received, says authentication error and says I am not authorized to mount that drive then I went back to terminal to fix it, and when I tried to elevate myself to SU:

I got this:
Code:
guy0203@guy0203-laptop:~$ sudo su
sudo: must be setuid root
guy0203@guy0203-laptop:~$

I don't know what to do now but I think I totally killed this OS. If so is there anyway to save things if I have to reinstall?