I downloaded this graphics package for under $5.00 on PC Crafter called "Howl'oween Fun" and quickly made up the game using a Print Master program I've got on my computer. I'm sure you could do up this game in Microsoft Word, using the Table feature - just plug in a graphic into each square of your table.
You'll need about 6-8 different Bingo cards, each with a different character placement. You don't want two alike! I used cardstock, but HEY, if this is last-minute then use what you've got!
Then make "cards" out of all of the characters.
I happen to have a GREAT laminating place down the road that I go to so I had mine laminated real nice so they'll last a good, long while. I definitely suggest you laminate your set if you're going to put the work and materials into the project!
DON'T FORGET THE CANDY!!!
Now you're ready to play! One person (probably Mom or Dad) draws a character from the cauldron and if someone has that character on their card, they put a candy on that space. Keep going until someone has 3 across, down, diagonally, or a full card!