I find Halloween quite an irritating time of year, but the Celt in me enjoys Samhain (pronounced "saw-when"). This is the start of the Celtic new year, and way back in the mists of time this was a celebration of the end of the harvest and the end of the summer. Some Celtic peoples believed that this day marked the time when the border between this world and the otherworld thinned, allowing the dead to reach through the veil between the worlds and touch the living. The living wore masks and costumes to immitate the dead in an attempt to make the spirits a little happier. They lit bonfires for cleansing rituals, and they even carved faces in veggies to ward off nastier spirits.
Of course, like most Celtic celebrations, the Christians had to come over and appropriate the holiday for their own purposes, and in this case, Samhain became All Hallows Eve in the Celtic realm since their celebration coincided with the Christian one. Since then, the original concept of Samhain has been bastardized into the ridiculousness we have now.
Anyway! There is some great Samhain music out there! This is one song I particularly enjoy, from Magica, and featuring the amazing keyboard work of 6 Fingers and Ana's wonderful voice. The lyrics are also beautiful.
On a more Halloweeny level, here is a great song by Manticora featuring gypsies and a fortune teller, and all that good stuff. This is my favourite song from their Black Circus Part 1 album.
And how about some Alice Cooper? He's creepy, though I know he isn't exactly metal. Here he is performing "Welcome to My Nightmare" - with the Muppets!
Enjoy, and if you live somewhere that celebrates Halloween, have a safe night!