I like Monster Mash when I was a kid, but I left novelty music behind. The song of Halloween to me a small little piano number by John Carpenter.
For me, it’s either this:
Ministry - Everyday is Halloween: http://youtu.be/DXtX9u7_6F8
Or this:
Bauhaus - Bela Lugosi’s Dead (Original): http://youtu.be/OKRJfIPiJGY