Heat oven to 325°F. Line 9- or 8-inch round cake pan with foil. In medium bowl, mix crushed cookies and butter; press firmly in bottom of pan. Bake 8 minutes.
Meanwhile, in large bowl with electric mixer, beat cream cheese on medium speed until smooth and creamy. Reserve 1 tablespoon of the sugar; place in small bowl. Gradually beat remaining sugar and the whipping cream into cream cheese. Add eggs 1 at a time, beating well after each addition. In reserved sugar, toss 2 chopped candy bars until coated.
Remove partially baked crust from oven. Sprinkle sugar-coated candy bar pieces over crust; press in lightly. Pour cream cheese mixture evenly over candy.
Return to oven; bake 40 to 50 minutes or until edges are set and center is almost set but jiggles slightly. Cool on wire rack 1 hour. Refrigerate at least 4 hours before serving.
Just before serving, in small microwavable bowl, microwave 1 chopped candy bar and enough milk on High 20 to 40 seconds, stirring every 20 seconds, until melted, smooth and drizzling consistency.
Use foil to lift cheesecake from pan. Remove foil; place cheesecake on serving plate. Cut into wedges; place on individual plates. Drizzle 1 teaspoon melted candy topping over each serving. Top with whipped cream and chopped candy. Store in refrigerator.