Halloween should be handled with great care. There are many dark pagan twists to it and many practices that do still happen today that are very much forbidden by scripture.
Personally, I will hand out treats with tracts with them. I rarely dress up, but if I do, I make sure it is not something that resembles evil/the occult and nothing scary. So no wizards, vampires, witches, or demons for me.
Fair enough, to each their own. (What you said about the pagan practices is true though and that's why I don't celebrate that part of Halloween.)