Song suggestions?

I used to be addicted to Guitar Hero, spending too much time mastering fake guitar. I convinced myself that playing the real guitar would be slightly more useful or slightly maybe more satisfying. Therefore, I bought a guitar last December. I took a month of lessons, but I wasn't sure what I was supposed to get out of it. I was just so horrible when I played, I felt there was very little the instructor could actually teach a brand-spanking-new player. I decided to just try to learn on my own until I felt I could get more value from a teacher.

It's been about five months and I definitely have improved, though that doesn't really say much at all. My fingers are still very weak and uncontrollable. In my life, I have never played the guitar or any stringed instrument and let me say that I find it significantly more difficult than the piano. I've described the piano as linear, but the guitar is two-dimensional. Right now, I can play basic chords and barre chords, though changing chords comes very slowly.

I'm always looking for "fun" songs that are easy enough for me to play so that others could at least identify the song, but challenging enough to help me to improve. Most are simplified versions of more complex guitar playing, usually involving basic chords that don't change too quickly.

Here are the songs that I can pretty much get through right now.

• Wonderful Tonight by Eric Clapton (my wedding song)
• Audioslave songs
  
  • I am the Highway
  • Like a Stone
  • Be Yourself
    
• Hotel California
• (The first half of) Free Bird
• In My Head by Queens of the Stone Age
• February Stars by Foo Fighters
• Your Touch by the Black Keys
  

I'm working on getting some Metallica songs too, including Enter Sandman and Seek & Destroy, which I have read are two of the easier songs. If you've had any experience with the guitar, please give me some more ideas. Otherwise, it gets pretty boring to play the same songs. Thanks!