Here are two pieces you should recognize from cartoons, but which you might have trouble putting a name to.
The first is "The Dance of the Comedians" from Smetana's The Bartered Bride.
Incidentally, Smetana is probably best known for his tone poem "The Moldau", which is part of a series called "Ma Vlast", or "My Fatherland". If you're not familiar with it, give it a listen -- it's one of the most beautiful pieces of music around.
The second piece is "Powerhouse" by Raymond Scott.