My dream Halloween party would feature a festive array of people in costumes, quality candy, good music, classic movies, and an overall spooky atmosphere.
My nightmare Halloween party would involve the guests becoming the characters as whom they are dressed. Of course, the threat likely would be higher if these characters posed any real danger, such as a supernatural being or super-powered villain. On the flip side, it may be interesting in the least to see such an event unfold.
Ah, the possibilities of a Halloween party. What fun (or fear) there is to be had.