It's hard to imagine a video opera collection without this superbly sung MET production of Bellini's I Puritani. Not that it's perfect by any means, but its excellences--most especially Anna Netrebko's electrifying singing and acting of Elvira--banish carping about other aspects of this memorable night at the opera. Netrebko is fragile from the start, her facial expressions and hand movements immediately conveying the girl's vulnerability. She has a mad scene in each act; the first when she real...