In a large, heavy saucepan over medium-high heat, combine sugar, butter or margarine and evaporated milk. Bring to a rolling boil; boil for 5 minutes, stirring constantly. Remove from heat; add remainng ingredients. Stir until smooth and chocolate is melted except Halloween candies. Pour into a greased 15" x 10" jelly-roll pan. Let stand overnight, or until firm. Cut into one-inch squares. Decorate with Halloween candies.