The Sunny Side of the Street (just belt it out in the open air)

The Happy Wanderer (a lot sappier, but enjoyed through the years) or Oh, What a Beautiful Morning (takes more wind; I can't sing it as well while walking).

Yip-I-Addy-I-Ay:
As I remember one episode of Al Capp's classic comic strip, beautiful Daisy Mae pours out in sorrowful songs her unrequited love for Li'l Abner into a hidden microphone placed by a team of crafty radio producers who make her the unwitting star of a nightly live radio show. Her beautiful voice and mournful lays inspire criminals to give up crime, misers to become generous, and all manner of people to turn to good works. But when Daisy Mae discovers that she herself is Li'l Abner's radio dream girl ("The Frail of the Lonesome Whine") she breaks into a joyful chorus of "Yip-I-Addy-I-Ay." Too happy to sing anything but cheerful melodies, she instantly alienates the entire radio industry. All over the nation, illdoers revert to evil ways with a new spring in their step. Worst of all her beloved Li'l Abner, like the rest of her audience, permanently lost interest the moment she strayed out of her genre of sad songs. Sic transit gloria.