1. Soften ice cream while preparing crust.
2. Place cookies in a food processor or blender; cover and process until fine crumbs form.
3. Stir in butter.
4. Set aside 1 cup for topping.
5. Press remaining crumb mixture into an ungreased 13x9 dish.
6. In a mixing bowl, beat milk and pudding mix on low speed for 2 minutes.
7. Gradually add ice cream; mix well.
8. Fold in whipped topping.
9. Spread over crust.
10. Sprinkle reserved crumb mixture over top, pressing down lighty.
11. Cover and freeze for 4 hours or overnight.
12. Remove from freezer 20 minutes before cutting.