This one's a favorite of my husband. My mom-in-law, Sharon, gave me the recipe. I believe she received it from her mom-in-law Maxine. I guess you could call it "Mother in Law's Pumpkin Dessert".
Preheat oven to 350 F. Combine 1/2 cup margarine, 1 cup brown sugar and 2 cups graham cracker crumbs. Mix together and put in 9 x 13 inch pan. Bake 20 minutes or until browned. Upon removing from the oven, crumble the crunchy mixture and when cooled, remove 1 cup for topping and press the rest in the bottom of the same pan.
Mix 2 cups canned pumpkin, 1 teaspoon cinnamon, and 1 teaspoon ginger. Add 2 cups whole milk. Mix in two 3 ounce packages of instant vanilla pudding. Gently fold in 8 ounces of Cool Whip. Spread mixture over crust. Chill thoroughly. Use additional Cool Whip and remaining crumbs for topping. Keep refrigerated.