Crush Oreo cookies. Save out 1/2 C. Mix the melted margarine with the cookie crumbs.Press into a 13x9 pan.Refrigerate for 1/2 hour. Mix 1 ( 8oz. ) cream cheese , 1 carton whipped topping and confectioners' sugar. Spread over crust and chill for 1/2 hour . Prepare pudding as directed using 1/2 cup Less milk than called for.Spread over cream cheese and chill . Top with the second container of whipped topping and sprinkle with the reserved cookie crumbs.