Pre-heat oven to 375°F.
Remove ice cream and cool whip from freezer and allow to thaw/soften.
Once cool whip has thawed, place back in refrigerator to stay cold.
In a small bowl, combine cracker crumbs, sugar and butter. 
Press into an ungreased 9 x 13-inch baking pan. 
Bake for 8 - 10 minutes or until lightly browned. 
Cool on a wire rack.
Meanwhile, in a large bowl, whisk milk and pudding mix for 2 minutes; mixture will be thick. 
Stir in ice cream; pour over crust. 
Cover, with aluminum foil, and freeze for 2 hours or until firm.
Remove from freezer, spread with whipped topping and sprinkle with crushed candy bars. 
Cover and freeze for 1 hour or until firm.
Unused bars should be immediately placed back in the freezer.