Directed by Michael Radford (best known for "Il Postino"), "The Merchant of Venice," which stars Jeremy Irons, Al Pacino, Joseph Fiennes and Lynn Collins, is better-than-average screen Shakespeare: intelligent without being showily clever, and motivated more by genuine fascination with the play's language and ideas than by a desire to cannibalize its author's cultural prestige. Judiciously trimmed to manageable movie length, this "Merchant" is, for the most part, faithful in letter and spirit to its source material. I say for the most part because "The Merchant of Venice" has become, over the past century, perhaps the most vexed single play...