As I write this message it is Halloween night across America and Dia de los Muertos in many Spanish-speaking countries.  I have lots of memories of trick-or-treating as a kid…and of lots of candy too.  
I don’t want to comment on whether Jewish families should participate or not, but rather to note that the macabre focus on the dead in Halloween is foreign to Jewish tradition.  But wait…what about Yizkor…and Yahrzeits…and Kaddish…and sitting Shiva?  It is true that Judaism has a way of memorializing the departed, but death is never glorified.  Martyrdom is not something to be admired, but seen as a sometimes necessary evil.  The Kaddish prayer is a praise of God and doesn’t even mention death.  The Book of Psalms tells us that “the dead cannot praise You [God].”  In other words, the preference is to be alive.
The Torah teaches us that we always have a choice.  Life and death are before us, so “choose life.”  We do not know what happens after we are gone.  We do not know for sure about the full nature of the spiritual world.  All we can know for sure (and even that in a limited way) is the world of creation in which we live.  
It is for this reason that Judaism never came up with a Day of the Dead.  Rather, each day is a day to focus on living life to the fullest.  May we all be blessed with many years of good health and life!  Lechaim!