I would recommend All is Well, but I could be biased because of my love for the song in general. It's a nice exercise if you've never played in that key before (I know I hadn't, and I haven't since), and once you get the hang of it, it's easy and it's good if you're showing off on the piano. :wink: I also find that Best Behavior is really fun to play, especially during the chorus and the piano solo.
Oh, and Birdie. It's repetitive, but I personally think it's oodles of fun to play. Yes, oodles.