PREHEAT oven to 325°F. Mix wafer crumbs, 1 Tbsp. of the sugar and butter; press firmly onto bottom of 9-inch springform pan. Bake 10 min.
BEAT cream cheese, remaining 3/4 cup sugar, flour and milk in large bowl with electric mixer on medium speed until well blended. Add sour cream; mix well. Add eggs, 1 at a time, mixing on low speed after each addition just until blended. Add dry pudding mixes; mix well.
BAKE 1 hour 5 min. to 1 hour 15 min. or until centre is almost set. Run knife or metal spatula around side of pan to loosen cake; cool completely. Refrigerate 4 hours or overnight. Remove side of pan. Top cheesecake with whipped topping and lemon slices, if desired, just before serving. Store leftover cheesecake in refrigerator.
serving size = 1/16 of cheesecake