Aaaah, Saturday and the hunt for a song I play when I'm happy. Honestly, nothing popped. But one I find cheery and always leaves me feeling chirpy would be The Lion Sleeps Tonight. I always thought it was a traditional song (aka folk song), however, if you're curious click on the song title (just above here) to go to the Wikipedia listing and see the interesting history this song has had on the copyright front.
It's been around awhile but more recent history is an appearance in The Lion King - movie and musical. A great movie that has much sentimentality tied to it as well.
The version I'm linking to today cracks me up with the animation of the hippo and the dog. I love the gestures both facial and body. Enjoy!
Oh, and I can never listen to it just one time.....there's always at least a second....or a third.....