Welcome to FT. I love SP, so here are a few of my favorites (hotel concierge will know them all):

Fiquiera Rubaiyat for SP's beautiful people watching, in one of the city's most relaxing and elegant rooms. Italian/Mediterranean food, not as great as the ambience, but above average. Spot, off Avenida Paulista is also a great place for beautiful (young and hip) people watching, and significantly less expensive. Brazilian-Italian-Fusion food. Food is good.

Personal favorite for best food in town: Antiquarius. Portuguese food and wine (best Portuguese wine list in Latin America).

Barbacoa (in Jardins) is what I consider to be the best churasscaria, although a lot of people prefer Fogo de Chao by the domestic airport.

Bargaço-For northern Brazilian food of all kinds, especially the "moqueca", a spicy stew with seafood, dende oil and coconut milk. Nice but relaxed atmosphere.

For something more informal and a little different, I like Mestizo...a Brazilian/Asian fusion place---very relaxed and mixed crowd, becoming more so later in the evening as the cachaça flows.

For Brazilian Japanese food, it's hard to go wrong, but Jun Sakamoto and Kabuki Mask are both great.

For a night out, you may want to try dinner and then the bar on the roof of the Hotel Unique. A young, hip and beautiful crowd. The hotel is great as well, if you are looking for a place to stay, although a ten minute cab ride from Avenida Paulista.