CJ Bowen gives you lots of links on Halloween here - mostly good. I found the Chick tracts article especially interesting, not having seen them much. For the quick summary of my take:
Halloween started as All Saints Day, to remember departed loved ones and martyrs of the faith. The date of November 1 began around 800, and the night before it became All Hallow's Eve, or Hallowe'en. This did NOT start as an occult holiday but as a Christian one. Or, if there were pagan practices going on (I've seen it asserted but not proven), then the church deliberately replaced the pagan stuff with the overtly Christian All Saints Day. This is what churches do today holding fall festivals or Reformation day celebrations on Halloween, to provide a positive alternative to the wickedness out there. We should reclaim this cultural ground, instead of ceding it to the wicked and shrill-ly denouncing it.
Practically, I'd encourage celebrations in families and churches to intentionally memorialize and thank God for three categories of people: martyrs, significant figures in church history, and loved ones recently gone to glory. Seasonally (church year), it is also very appropriate to consider the coming final harvest of the earth. (See Revelation 14:12-20 for an appropriate, but scary Halloween image!) Thanksgiving hymns can begin at this time, instead of only using them one day a year.