Sean Astin, the 33-year-old actor who won fame playing the title rtole in "Rudy," has been named Bacchus XXXVII. Astin will lead the 38-float procession along the traditional route on Feb. 6 at 6:30 p.m. A special new feature of this year's parade will be the return of actor Elijah Wood, who served as Bacchus XXXVI last year. Wood will ride a Returning King's float.