The graveyard scene of the Haunted Mansion is a showstopper any time of the year.  The change in tone from morbid to merry and that ever-so-catch "Grim Grinning Ghosts" tune are an irresistable part of why this classic E-Ticket attraction is such a beloved favorite.  And when Halloween Time comes (and continues into the Christmas season), the Haunted Mansion takes on a Holiday monicker, adopting a Nightmare Before Christmas  overlay that transforms the graveyard into a festive party that celebrates both holidays collided together!  The cemetery scene looks fantastic under a blanket of snow, draped holiday lights, and the happy haunts enjoying the spirit of the season.  And wouldn't you if your environment was so beautiful?