I don’t have time to defend celebrating Halloween in a distinctly Christian or Reformational way. We had our “traditional” pot pie and German beer, followed by a rousing liturgy of children chanting the 5 Solas (while banging toy hammers), Bible readings, and hymns. Perhaps I’ll post that liturgy later.
I was struck, however, by the attempt of local churches to provide an alternative to Halloween. I drove past one church which had set up inflatable jump-houses and various other fun, exciting things for kids to do. All in the name of an “Old-Fashioned Fall Fesitval”. Yes, jump around like your grandpappy used to!
But, why celebrate Fall? What Biblical reason do we have to celebrate the seasons? Sounds like ancient paganism to me … Our family has a long way to go, but we are trying to celebrate the Church Year with more feasting and more candy, not less. Last night, we celebrate the Communion of the Saints and God’s mighty acts in history, as well as his providence over the seasons.
So much of the Christian reaction to what the world has done to Church holidays is still too worldly. Like contemporary Christian music, or some “Christian” curricula, we just copy the world’s way of doing things without stopping to think about deeper meanings.
Studium et Liturgica 
One reason I can think of for celebrating the Fall is that God made it and we ought to give thanks. But I wholeheartedly agree with your feeling here that in giving up Halloween and celebrating Fall, what have evangelicals achieved? We’ve got rid of the evil twist of Halloween but have we reformed? Nay! How about celebrating All Hallow’s Eve, as such, and All Hallow’s Day, as such. Give God thanks for All Saints, remembering His goodness to them and us through the ages. Also, I think it good to celebrate living saints, not dead ones. This includes all those saints who have already gone on to be with Jesus.