Crush 16 cookies; toss with the butter. Press into an ungreased 9-in. square dish; set aside.
In a large bowl, beat the cream cheese, peanut butter and 1 cup confectioners' sugar until smooth. Fold in half of the whipped topping. Spread over crust. Sprinkle with peanut butter cups.
In another large bowl, beat the milk, pudding mix and remaining confectioners' sugar on low speed for 2 minutes Let stand for 2 minutes or until soft-set. Fold in remaining whipped topping.
Spread over peanut butter cups. Crush remaining cookies; sprinkle over the top. Cover and chill for at least 3 hours