Fun Halloween specials for a general audience?
Spookier than Nickelodeon fare but not too scary. The Tim Burton stuff, Young Frankenstein, Coraline. It's The Great Pumpkin, Charlie Brown is good for the shorter attentions spans.
Would prefer to stay away from serialized TV episodes. Better to have something that can stand on its own. But stuff like Simpsons Treehouse of Horror might work, since they're often done in the Twilight Zone format of self-contained universes.