Lunch on State Street= people viewing galore. Natural Cafe, The Chase, Pierre LaFond, Left at Albuquerque. None of those would be where I'd go.
I always reccomend the Minnow at the harbor. You can leave the freeway and easily arrive to park at the waterfront- right infront of the City College track, and walk along the boats and get one heck of a lunch with a cold beer- then walk the along the flags and enjoy the view. The burgers, sandwiches and fish and chips rock- and did I mention the cold beers?
At the harbor as well, everybodys fav Brophy Brothers (good luck on a Sunday), the Sushi a Go Go (very good-but dinky), and the Endless Summer (don't bother).
The Maritime Museum is right next door, and if either of you is any fan of anything water related- a great place to spend a few hours checking out boating history, naval history and diving history, as well as surfing history as well. I am minimally interested in these things, and you couldn't get me out of there!
Across the harbor, on the Stearns Wharf- is SBShellfish, which is also a great lunch spot- but I bet it will be packed- though it is worth the wait, and they do have a to go window with lots of seating- just keep your hands very close to your food, the seagulls are ruthless.
Arrive in SB, and take the 154 up the hill, and on top is Cold Springs Tavern- Sundays are wild and crazy- music and people watching galore- tri tip sandwiches and cold beer. Probably will be packed, so personally, unless you are looking for the scene sure to happen, pass this time. Good food in the restaurant, to be sure.
If you are looking for a fancy, no holds bar, place to impress, San Ysidro Ranch, the Stonehouse would be great, out on the deck. The Four Seasons too, along th ebeach in Montecito- gives expensive a new name- but sure to impress.
Have a great afternoon, and remember to leave early, and stay late to miss all the others from down south sure to be doing the same thing!