In a small bowl, combine cracker crumbs and butter; set aside 2 tablespoons for garnish. Press remaining crumb mixture onto the bottom of an ungreased 10-in. spring form pan. Place on a baking sheet.

Bake at 375° for 8 minutes, or until edges begin to brown. Cool on a wire rack.

In a large bowl, combine the ice cream or frozen yogurt, milk, dry pudding mixes and vanilla; beat until smooth. Fold in half of the whipped topping. Pour over crust.

Cover and freeze for 1 hour or until firm.

Spread with remaining whipped topping and sprinkle with reserved crumb mixture. Freeze for at least 3 hours or until firm.

Remove from the freezer 15 minutes before serving.