MIX finely crushed cookies and the margarine until well blended. Press firmly onto bottom and up side of 9-inch pie plate to form crust.
SPREAD ice cream into crust. Freeze at least 6 hours or until firm.
TOP with the whipped topping just before serving; drizzle with fudge topping, then sprinkle with the coarsely crushed cookies. Store leftover pie in freezer.