Put gingersnap crumbs, graham cracker crumbs, granulated sugar, and melted butter in a bowl. Use a fork to stir until combined.
Press into a 9×13 inch pan. Set aside.
Cheesecake
Beat softened cream cheese until smooth. Add granulated sugar and vanilla. Beat until smooth, scraping the sides of the bowl as needed.
Lightly whisk four eggs in a small bowl to break them up but do not beat them. Stir the eggs into the cream cheese mixture just until combined. Do not over mix or beat.
Remove three cups of cheesecake batter and spread over prepared gingersnap crust.
Place in the freezer for 20-25 minutes.
Add pumpkin puree, cinnamon, and nutmeg to the remaining batter. Mix until combined.
Remove pan from freezer. Pour the pumpkin cheesecake batter over the hardened plain cheesecake layer.
Bake at 350˚F for 45-50 minutes. The center should be set but still jiggly.
Place on a cooling rack to cool completely.
Cover and chill in the fridge for 5-6 hours or overnight.
Remove from fridge and cover with whipped cream or Cool Whip. Sprinkle with cinnamon. Store in the fridge.