The season’s two biggest franchises have more in common than bazillions in ticket sales: Wizards, elves, trolls, and animated trees crop up in ”The Lord of the Rings” and the two ”Harry Potter” movies. ”Rings” director Peter Jackson moved a jumbo spider — not unlike the one in ”The Chamber of Secrets” — from ”The Two Towers,” the second in J.R.R. Tolkien’s series, to next Christmas’ ”Return of the King.” [More]