BELLS ARE RINGING: The get-up in New York's get-up-and-go comes from the switchboard operators of Susanswerphone. Need a wakeup call? Your appointments? Encouragement from "Mom"? A racetrack bet? It all comes from that dutiful nerve - or noive - center that keeps enterprises enterprising and, maybe, wedding bells ringing. Starring Judy Holliday and Dean Martin.