It is easy to make a day or two out of the wharf and pier 39. It is interesting and touristy, but a must in your first trip to the Bay Area.
Some places you may try are Scoma's, the sourdough factory, and not to far away is ghiradelli square.
I love fresh spring rolls and Fish Restaurant makes them outstanding. They are crispy and spicy, fresh and delicious! If you come here try at least one.