In 'Elf' (2003), who plays Buddy the elf?

In 'Citizen Kane', what is "Rosebud"? In 'Home Alone', what is the name of the boy left behind? In 'A Christmas Story' (1983), what gift does Ralphie want? Which actor played George Bailey in 'It's a Wonderful Life'? In 'The Santa Clause' (1994), who plays Scott Calvin? In which film does Clark Griswold decorate his house with 25,000 lights? Who plays Clark Griswold in the 'National Lampoon's Vacation' films? In 'Groundhog Day', in which town does Phil Connors get stuck reliving the same day?