I made a very similar recipe--identical, actually, except that it had no ghosts or gummy worms--that I found in a Jello cookbook and it was the hit of my Halloween party! Try ringing the "graveyard" with a candycorn fence, and scatter some candy around between the tombstones.
I absolutely LOVE this recipe. It is so cute and fun for kids to help make around Halloween. I have even buried a mini coffin in the pudding for a party.