Combine crumbs, sugar and margarine; press equal portions onto bottoms of 24 lightly greased or paper lined muffin cups. In a large bowl beat cheese until fluffy. Gradually beat in sweetened condensed milk until smooth. Add eggs and vanilla mix well. Spoon equal amounts of mixture (about 3 tablespoons) into prepared cups. Bake 20 minutes at 300 degrees or until set. Cool. Chill. Top with filling.