There are two distinctly different places to eat in this neoclassic Nob Hill showplace. The Dining Room ($$$$), which is formal and elegant, with French windows, the finest linens, and an encyclopedic wine list, serves only prix-fixe French seasonal dinners, priced by the number of courses (three to five). The Terrace ($-$$$), a cheerful, informal spot with a large garden patio for outdoor dining, serves breakfast and lunch daily and a Sunday jazz brunch.