You don't need a car in San Francisco. In fact, having a car is detremental because it's gonna cost you to park it everywhere you go. Just stand on any corner and some type of public transportation or other will come by every 15 minutes to take you where ever you want to go.
As for restaurants, I just happen to be going there for New Years from the 21st to the 25th of February and the restaurants that are on my "don't miss" list for this trip are Dottie's True Blue Cafe
and Sears Fine Food
for breakfast; Bistro Boudin
, Zuni Cafe
, and Fog City Diner
for lunch; and Scoma's
and Ana Mandara
for dinner. I wanted to try Gary Danko
because it was voted best restaurant in San Francisco several times, and it's within walking distance from my hotel, but they've got a 2 month waiting list. Maybe the concierge at my hotel can get me in if I beg real nice, but I am not counting on it.