Does it have to be just one hero and just one villain?
All-Time Favorite Movie Hero: Samwise Gamgee from last of the "Lord of the Rings" movies, "The Return of the King". No question about it.
Runner-Ups: Dirty Harry from, well..."Dirty Harry", John McClane form the "Die hard" movies, Jack from "Legend", Prince Ashitaka from "Princess Mononoke/Mononoke hime", Aragorn from the "Lord of the Rings" movies, and Will Turner from "Pirates of the Caribbean: Dead Man's Chest".
All-Time Favorite Movie Villain: Alec Trevelyan/Agent 006/Janus from the first James Bond movie of the 1990s: "Goldeneye".
Runner-Ups: Blofeld from several James Bond movies, Darth Vader (do I really need to tell anyone what films he's from?), The Lord of Darkness from "Legend", Capt. Barbossa from "Pirates of the Caribbean: The Curse of the Black Pearl", Hans Gruber from the first "Die Hard" movie, and Jafar from "Aladdin".