Crush 16 cookies; toss w/melted butter. Press in bottom of ungreased 9 x 9 pan. In mixing bowl, beat cream cheese, peanut butter and 1 cup powdered sugar until smooth. Fold in half of Cool Whip. Spread over crust, sprinkle with peanut butter cups.
In another bowl, beat milk, pudding mix and remaining powdered sugar on low speed for 2 minutes. Fold in remaining Cool Whip. Spread this mixture over peanut butter cup layer. Crush remaining cookies and sprinkle over the top. Cover and chill for at least 3 hours.