New York has rarely seen a pizzeria that looks anything like Dean’s Pizza, which opened four weeks ago on the Upper West Side. Built into the refurbished grand ballroom of an old hotel, it has high ceilings and ornate moldings that elevate the act of ingesting cheese and sausage. But the pizza itself is no surprise: Co-owned by Mirene Angelis and Nick Tsoulos, the place is the latest effort from the city’s most productive pizza-making family, the extended Angelis-Tsoulos clan.