If you need a quick lunch. In-N-Out doesn't get the respect it deserves on these boards.. But I love it. Best fast food burger in existence.
Also, every trip home, I eat at Rubios 3-4 times. Lobster Burrito, and Fish taco. Amazing. You'll probably find fish tacos a lot of places, but that's my favorite place even though its a chain.
My favorite place for nice seafood restaurant is "The Fish Market". Its at the end of the Embarcadero. Great views, GREAT food. They have a more casual restaurant below and a nicer restaurant up top.
And Karl Strauss is a great brewing company. I concur with all those remarks.