For the pie crust, preheat the oven to 350°F. Place the Oreos in a food processor or blender and blend until they have turned into crumbs. Should be about 2 cups.
Stir in the melted butter, sugar and salt until combined. Then press into a 9-inch pie dish. Use a measuring cup to press firmly. Bake for 10 minutes. Set aside to cool completely.
Place the cream cheese and peanut butter in a medium size bowl and beat until smooth with an electric beater. Add the powdered sugar in and mix until smooth. Then fold in the whipped topping and vanilla. Spread into pie crust.
Top with chopped Reese's. Then chill in the freezer for at least one hour. Remove just before serving. Slice into 10 slices.
To make this pie a no bake recipe (and even easier), you can use a store bought oreo crust.