I've hosted themed Halloween parties in the past (albeit for college students, but it's basically the same, sans alcohol).
Two years ago, I did "A Hitchcock Halloween." I rented three Hitchcock flicks-- Vertigo, Rear Window, and The Birds-- and stuck Vertigo in the DVD player.
There was music, and drinks, and food for a while, but when enough people arrived, I started the film. Not everyone watched all the time, but it gave people something to do, especially if they didn't want to socialize.
A friend of mine started a drinking game, which made more people settled down to watch the film. If I were you, rather than using alcohol, you can use candy for your drinking game.
Last year, it was a Rocky Horror themed party. I made meatballs and said they were from Eddy Scott's corpse. Rocky Horror was playing, and even people who weren't watching it partook in "The Time Warp."
After Rocky Horror was over, some folks started playing Resident Evil 4 on my GameCube.
The point is, you can provide entertainment, but generally people will find their own ways to entertain themselves. I'd recommend making good food and drinks, setting up a few activities, and letting people figure out what they want.
A theme I've always wanted to do was Nightmare Before Christmas. You could try that out.
um it depends on how artistic you are.it seems like zombies are a big thing this year.Vampires seem to be big as well.But the zombie thing is a good idea.you can go online and find out how to make fake blood and all.Heres an picture to give you an idea
I have had a few parties. costume contests always get the spirit going. one year my room mates and I made a scary scavenger hunt (putting hands in gross things, things they're scared of, etc.). Umm, until you're 21 I can't give ya more advice :)
You could do Best Coustume contest,a carnival theme and for everybody you could do a contest for best person who can do the Jerk.You could also do scary stories where you are in pitch black dark or just sit in the dark and see who screams first.Get like a creepy sound cd hide it somewhere.E-mail me if it not good enough!