In a small bowl, combine cracker crumbs and butter; press onto the bottom of an ungreased 9-in. springform pan. Bake at 350° until lightly browned, about 5 minutes.
Place the cream cheese, blue cheese, spreadable cheese, sour cream, eggs, milk, sherry and pepper in a blender; cover and process until blended. Pour over crust. Place pan in a large baking pan; add 1 in. of hot water to larger pan.
Bake until center is almost set, 50-55 minutes. Remove springform pan from water bath. Cool on a wire rack for 10 minutes. Carefully run a knife around edge of pan to loosen. Refrigerate overnight. Serve with crackers.