There is no Halloween in Hungary... But of course most Americans do celebrate this holiday beginning in grade school where the cycle of Holidays is usually played out througout the year. For some this is an opportunity to wear a mask and costume and play at some alter-ego for a while. Usually this is playful and silly and there is no harm in it at all.
Personally, I like the pumpkins and gourds, the harvest festival aspect of the American Holiday. I also like the spiritual aspect of it, the idea that at this time of year this world you can celebrate or communicate with your ancestors.
What I can do without is all the fright and gore, the Haunted Houses, the way this celebration has been perverted into something evil rather than reverent. There is no good reason as I see it for EVIL to be associated with this holiday or time of the year, as if evil doesn't exist all the time. I don't think the celebration of ancestors or trying to communicate with them (this is usually through psychicism) is evil either. For most of us, going through the family album or old scrapbooks is good enough.