All Hallows Eve
My wife has come to enjoy American-style Halloween quite a lot. In Poland, and the rest of Europe, it is celebrated quite differently. The eve of All Saints Day, called the Day of the Dead, is a time when families in Poland go to their family graves, sweep them, clean them up and put lots of candles on them. At night, which is usually crisp and cold, the cemeteries are quite beautiful, glowing with the light of thousands of candles.
A Polish academic who lived in America once told me that American Halloween just shows that Americans turn everything into a party - even death.
A friend remarked, "So why not? It's going to happen anyway whatever you do, so why not party?"
Sadly, the custom of Trick or Treating appears to be dying out. Though there has never been a single authenticated case of poisoned treats, or apples with razor blades, or any of the other Halloween urban legends, nonetheless people have become paranoid to the point that they'd rather take the kids to a supervised party.
Observinging something like the European tradition would also be nice, but who in America keeps family gravesites where generations of relatives are buried? Because my father and grandmother had an interest in geneology I was able to look at quite extensive family history charts, and I noticed something that astonishes Europeans. For over three hundred years, almost nobody in my ancestral line was buried in the same place he was born and seldom are two generations born in the same place. I imagine that's probably quite typical of Americans.