I drive up to San Francisco every other month. It is such a fun place to see art. Forget about a car. You don't need one. Just hop on and off the Muni and have a great time. You MUST visit the DeYoung museum and walk through the park, go up to the top of the museum and look out at a 360 degree view of the city. They have great shows and a FAB book store.
San Francisco also has a great craft museum and book art museum plus a modern art museum and so much more, but the DeYoung is my favorite because it is in the park, so you can take a lunch and sit outside after your visit. Enjoy! Here's some websites for the DeYoung, craft museum, and the book art center: - Katrina in L.A., CA