The Bush years are coming to a close, Congress is no longer giving him a blank check, and the war is deeply unpopular. We have been under a cloud for most of this decade. As we begin to enjoy the light of the returning sun, we need to fill our lungs with the lightness and laughter of Chekhov's Uncle Vanya, a comedy about a bitter, ineffectual man and his botched attempt to commit murder. (Intiman Theatre, 201 Mercer St, 269-1900. 7:30 pm, $44.)