Hmm.. I can't remember. It was either "Dead Letters" by The Rasmus or "Ocean Avenue" by Yellowcard.
After that I didn't really listen to music until I bought "Stadium Arcadium" a few years later.
Not until recently when I got an ipod did I really get into music. Due to having never really bought any before the age of 18, you can imagine the horror when I got my bank statement after plundering itunes, not thinking how much I was spending.