The Marina District in San Francisco is about as walkable as it gets. You can walk to everything. The streets are some of the most beautiful in all of San Francisco with nice healthy trees and well kept home fronts (the architecture here is really attractive). You have restuarants and grocery stores (they have their own Safeway) all with the Marina so they are less than a mile away no matter where you live.
Several Muni (bus) lines serve the Marina, so you don't need a car to even get to work. You really don't need a car for the area at all. Though if you have one, most of the homes have garages--which is another convenience of the area.
