Advantages: Great Fun
Disadvantages: Ooohh it is scary
Contrary to popular belief in the South of England, Halloween is NOT an American import.
It is as British as bagpipes, literally.
Halloween has been celebrated for centuries in Scotland, Northern England, Wales and Ireland.
Some would say the Halloween celebrations originated in Ireland and others Scotland, this confusion probably lies with the fact that there has been much migration between the two countries over the centuries, but the concensus seems to be that it was Ireland who began this. The idea that it is an American thing, revolves around the humble pumpkin and the phrase 'Trick or Treat.
Halloween was EXPORTED from Scotland and Ireland to North America by those moving there from those countries.
Scottish and Irish children would go 'guising' at Halloween, that is they would be in disguise and they would go from door to door performing for their neighbours - they would perform a 'party-piece', that is a song, a dance or some sort of routine, perhaps tell a joke, and be rewarded with fruit or nuts. However, there would be the occassion when some miserable old so-and-so would not treat the children, so a revenge would be carried out. THIS is where the notion of the Americanism TRICK or TREAT grew out of.
Now the pumpkin? Pumpkins grow well in the South of England, but not in the rest of the UK.
Scottish and Irish children had their lanterns but these were made from turnips (or swedes as they are known in Southern England - likewise, what the Scots call swedes, Southerners call turnips).
so to clear up the confusion, whether you call it a turnip or a swede, it was the BIGGER of the two that Scottish children, used to make thier lanterns. In my opinion they are more suited; they are more robust. last longer, are unusual and odd shapes, sometimes 'hairy' and a darker colour AND when you scoop out the inside, even though it is much, much harder, it doesn't stink, isn't slimy and messy and the cooked results taste far superior to pumpkin. No really, mashed turnip (English Swede) with salt and pepper and a little sugar is delicious. So the original lantern was a Scottish Turnip, over the years the Scots and Irish tradition as practiced in America, adopted the pumpkin as it is a more well used and known vegetable over there, and indeed, there is no arguing that its shape lends itself well to the idea of a lantern. Thanks to the media, which dictates our lives and American films (which Brits seem to soak up as gospel) such as the Halloween series, here in the South of England, where Halloween, hasn't been a prolific thing on the calender, it is seen as American.
Summary: Halloween is NOT an American import
Image taken from Flickr account of uglyagnes under the creative commons scheme