In a medium bowl, stir together cookie crumbs, melted butter, and sugar. Press into bottom and up sides of a 9-inch pie pan.
Bake for 8 to 10 minutes and let cool.
In a large saucepan, combine marshmallows, pumpkin, cinnamon, salt, ginger, and nutmeg. Cook and stir over medium heat until marshmallows are melted. Let mixture col to room temperature.
Fold whipped topping into cooled pumpkin mixture until evenly mixed. spoon into prepared crust.
Refrigerate for at least 2 to 3 hours before serving.
If desired, serve with additional whipped topping.