SEASON FINALE: This series has been harmless enough, in a Candid Camera type of way, and, a as a geriatric version of Punk’d, slightly less mean-spirited. But tonight, there’s a more persuasive reason to tune in: For this final show of the season, the scheduled guest prankster is Ed Asner, who first co-starred opposite Betty White when she played Happy Homemaker Sue Ann Nivens to his Lou Grant on The Mary Tyler Moore Show (pictured).