Was Hamlet 16 or 30? There’s no completely accepted conclusion to the question. If he’s 30, then having a 42-year-old actor playing him — Michael Sheen, pictured, in a new London production — is on the edge of acceptable. But Sheen’s screen age — he played a 44-year-old Tony Blair in “The Queen” five years ago — seems much too withered for him to essay the Danish prince. The issue of Sheen’s age hasn’t prevented the production from scoring some good reviews. Doubt this is coming to the U.S., though.