To its credit, the 3-D, computer-animated musical Legends Of Oz: Dorothy’s Return sidesteps the smirking, Shrek-y snark that mars so much kiddie cinema. The Tin Man (Kelsey Grammer) doesn’t wear sunglasses or breakdance or anything. There’s no nagging, desperate hipness. In its place is an old-timey earnestness, sincere to the point of boredom as G-rated Legends charts the quest of Dorothy (Glee’s Lea Michele) to thwart an evil jester (Martin Short) who wields the powers of the late Wicked Witch. But it’s short on jokes and hampered by unmemorable musical numbers (including one about building a boat), and the film’s niceness can’t overcome the dopey tedium.