When Sistina Restaurant moved across town, close to the Met, it found its new home in a palatial townhouse with just the right mix of old bones and room for fun. The main dining room, once a wood-paneled library, now shares space with a winter garden where Fortuny fixtures and Murano glass jellyfish float from the ceiling in suspended dance. Upstairs, the private dining rooms run with their themes—Nabucco in one, Gallinarum in the other—with artists brought in to splash the stories across the walls. A stair hall, no longer needed for stairs, has been turned into a wine cellar, bottles climbing from floor to ceiling and along the treads, ready for the next table that needs a pour.