Coming this week: “Suburgatory,” my favorite new series. But the week also offers big mysteries about returning series:1. How many viewers can “Two and a Half Men” hold on to after 28 million sampled the first show without Charlie Sheen last week? We’ll find out when the second episode pairing Jon Cryer and Ashton Kutcher airs at 9 p.m. Monday on CBS.2. Will Melissa McCarthy’s Emmy victory do good things for “Mike & Molly“? The CBS sitcom starts its second season at 9:30 p.m. Monday, and “2 Broke Girls” shifts to 8:30 p.m. Monday. McCarthy also hosts “Saturday Night Live” this week on NBC.3. Will “The X Factor” bring in more viewers? The singing contest from judge/executive producer Simon Cowell did only so-so ratings last week, not numbers in the same league at “American Idol.” Two-hour editions continue at 8 p.m. Wednesday and Thursday on Fox.4. Is “Dancing With the Stars” showing some viewer fatigue? We’ll learn more as Chaz Bono, HLN host Nancy Grace, David Arquette and others perform at 8 p.m. Monday on ABC. The results show airs at 9 p.m. Tuesday.On the new series front: ABC’s wacky “Suburgatory” supplies further proof sitcoms are coming back. The show also gives us Tessa (Jane Levy), a delightful 16-year-old furious that her single dad (Jeremy Sisto) has moved the family from New York City to the ‘burbs. Cheerfully sarcastic Tessa detests the gossip, nose jobs and mean girls, but it’s a funny spot populated by goofy adults.Cheryl Hines and Alan Tudyk play the chief goofs hilariously. Levy and Sisto have a lovely rapport. But Levy is the main news: A star is born. Tessa might hate where she lives, but ABC has put the comedy in the best possible spot: 8:30 p.m. Wednesdays, between “The Middle” and “Modern Family.”This fall, the new sitcoms (“Suburgatory,” “2 Broke Girls,” “New Girl”) impress more than the lavish new dramas. That’s true of Fox’s “Terra Nova,” which debuts with two hours at 8 p.m. Monday. This show, a rare family drama, feels like “Swiss Family Robinson” meets “Jurassic Park.” A desperate family from the polluted Earth of 2149 agrees to go back to prehistoric times to try to help save mankind. The family members soon witness the wonders of the unspoiled Earth, the majesty and terror of dinosaurs, and the frictions among the colony they have joined. The production is lavish, but the writing is predictable. Still, Steven Spielberg is behind the show.“Hart of Dixie,” at 9 p.m. Monday on The CW, is a fish-out-of-water story, a medical show and a romantic comedy all rolled into one. A New York doctor (Rachel Bilson) goes to the rural South to work on her bedside manner and serve the colorful citizenry. Orlando’s Scott Porter plays a dashing attorney. Porter has two classics to his credit: “Friday Night Lights” and “The Good Wife.” But pleasant, predictable ”Hart of Dixie” isn’t a third.“How to Be a Gentleman,” at 8:30 p.m. Thursday on CBS, gives us the improbable friendship of an uptight writer (David Hornsby) and a crude trainer (Kevin Dillon). This is not the beginning of a beautiful relationship, but the start of a deeply irritating sitcom.“All My Children” has left the ABC schedule. “The Chew,” a food show, moves in at 1 p.m. Monday and tries to make us forget Erica Kane and Pine Valley. Good luck with that.