y'all are gonna laugh at me and reply with the rollin eyes smiley, but MMMBop will get me up and jumping around any time! I was wicked stressed for finals last year and MMMbop came on the radio and I flipped shit because I hadn't heard it in ages! It was such a great release to be jumping around my room and realized I still knew all the words!
Other fun songs include: Are You Happy Now by Meech (it's a fun angry song), Slave For You, OOOps I Did It Again, and (recently) Toxic by Britney, Going Under by Ev, and Two Step, Ants, So Much To Say, Pig, and Watchtower by DMB
Edit: How could I forget Weezer?
Buddy Holly and Keep Fishing!