What is The UMC's view of Halloween?

Cross at Lake Junaluska - Waynesville, NC

The word "Halloween" (or "Hallowe'en") means "the evening of Hallows."  "Hallows" is an older English way of saying "saints" — so, the Evening of Saints. 

But why "the evening?" Many ancient cultures in the Mediterranean world and the Middle East, including Jewish cultures, understood the day as beginning with sunset rather than sunrise. This is why Genesis one says, "And it was evening, and it was morning, day one." (Genesis 1:5). Because the day began with sunset, the first worship service of a given day would be the evening service.

Put it all together and Halloween refers to the first service of worship for All Saints Day. That day falls on November 1 in the Western Christianity. That's why All Saints Eve (Halloween) is observed on the evening of Oct. 31.

Read more at this link.