This morning on WVTF Public Radio, Seth Williamson played Franz von Suppe's "Light Cavalry Overture" and I know it will likely annoy him to hear this, but every time I hear the melody from that piece, a vivid picture of Dudley Do-Right riding backwards on his horse comes to mind. (Go to the 2:29 mark in the attached "Light Cavalry" to get the melody and then listen to Dudley's tune you'll see what I mean. The two melodies are slightly different, but I don't care. They're close enough.)
Walt Disney and Warner Brothers educated a generation of kids in classical music (though they had nothing to do with Dudley) and we must thank cartoons while simultaneously cursing them. Mickey Mouse in "Fantasia," a host of outlandish Warner characters, including that damn operatic frog ("One Froggy Evening"; OK, it's Ragtime; it's still cool) and the signing whale, come to mind.
Classic Americana: go to the lowest common denominator and make it memorable, like the GE light bulb and Pachalbel's Canon.