Mix with butter; press firmly onto bottom and 1 inch up side of 9-inch springform pan. Set aside. Coarsely chop 24 of the remaining cookies; set aside.
Sprinkle gelatin over milk in large saucepan; let stand 1 min. Cook on low heat 3 min. or until gelatin is completely dissolved, stirring constantly.
Add chocolate chips; cook until chips are completely melted and mixture is well blended, stirring frequently.
Place saucepan in bowl of ice water; let stand 8 to 10 min. or until gelatin mixture is slightly thickened, stirring frequently. Gently stir in chopped cookies and the whipped cream. Spoon into crust.
Refrigerate at least 6 hours. Halve remaining cookies. Arrange on top of cake just before serving. Store leftover cake in refrigerator.
