Preheat oven to 350 degrees. Combine crumbs and margarine; press firmly on bottom of 9-inch springform pan. In large mixer bowl, beat cheese until fluffy. Gradually beat in sweetened condensed milk until smooth. Beat in eggs then sour cream and vanilla. Pour into prepared pan. Bake 50 to 55 minutes or until lightly browned around the edge (center will be slightly soft). Cool. Chill. Garnish as desired. Refrigerate leftovers.