The way I see it, there's two ways to go on this -
1) Fun - wines with names like Vampire, Dracula's Blood, Werewolf, Ghost Pines.
2) Quantity and Convenience - I'm talking box wines. No, not Franzia, (although a 5 litre box of Cab got us through the better part of a week camping in Red River, NM this summer). There's a nice variety of 3 litre boxes out there like Black Box, Bota Box (Delicato), Hardy's, Boho, and other's. You can't take these wines too serously, but then Halloween is one or our less serious holidays. These are the party wines for party food/snacks. And, do you really want to open a $12 bottle of Chardonnay or Cab to fill the travel tumbler you're carrying with you as you walk your trick-or-treaters around the neighborhood.