Answering some previous posts, and adding other thoughts:
Reviewing the Situation - Oliver!-- is a great song, although I have a hard time treating Fagin as the villain. He's funny and he does feed a bunch of homeless kids. I think the villain in Oliver is Bill Sykes, rather than Fagin.
Heffalumps and Woozles- Winnie the Pooh -- what a GREAT song. I didn't recall any villains in the short movie, however.
"Stars", "Soliloquy" from Les Miserables -- I think Javert is indeed the villain in Les Mis; Thenardier, although an utterly revolting character, is too silly to be completely villainous. I'm crazy about his "Master of the House," and "Thenardier Waltz," however -- especially the reprise, where he sings, "This one is broke, that's one's a Jew, this one is queer, but what can you do?" As an aside, the odious Thenardier seems more accepting of gay people than are most members of the Republican party.
"Mary Poppins" -- Stage production: "Brimstone and Treacle."
Also, "Poor Fool He makes me Laugh," is sung by Carlotta in the "Phantom of the Opera." I don't see her as the villain, but as more of a comic foil. If the Phantom himself is a villain, my favorite Phantom song AS VILLAIN rather than unrequited lover is "Down Once More." (My favorite song in the universe is the love song "MOTN," where the Phantom doesn't sound very villainous at all.)
Another great villainous protagonist song, which happens to be hilarious, is "Have a Little Priest," from "Sweeney Todd."
You alone can make my song take flight.