Last year was my first Otakon, too. I had such a blast!
I think my favorite part -- aside of Squall cuz I just melted when I got my Vamo alla Flamenco (my favoritest song EVERRRRRR) -- was Twinkie Sushi on Friday morning. I was so sleepy and bleary-eyed, and then I just got a sugar RUSH and I was running around like a headless chicken all day. ^_^