"People Got To Be Free" by the Rascals. Recently appropriated for some commercial, in a truly awful cover version. But the original was great.

"Pretty Little Angel Eyes" (50's doo-wop; don't remember who)

"Rise Again" by the Rankins

"Summertime Blues" -- either the original by Eddie Cochran, or the cover by the Who; Cochran's "C'mon Everybody" also qualifies

"La Bamba" by Richie Valens -- a little shopworn, but still a great one

"Oh Boy" by Buddy Holly

Actually, there's lots of good, happy stuff to choose from, especially when you dip into 1950's rock and roll. Smile!