IMHO, "Jack in the Box" is groce, but love In-and-Out Burgers...they do make them to order after you have ordered. The menu is very limited so be sure you want the burgers. (maybe I can't eat at Jack since several people died after eating there several years ago...believe they died in Wash. state...look up the details on google) In fact, I only ate there once it was so terrible and most Americans laugh at it...those I know do at least.
Yes, Rubio's is wonderful too, and Baja Fresh is almost as good. Taco Bell is not Mexican food and it's groce..it's some sort of "Mexican food for the US masses." . Mexican food that is freshly prepared with quality ingredients is healthy....avoid Taco Bell. If you get time, drive down to Santa Barbara and eat at the taco stand, La Supra Rica (was Julia child's favorite restaurant),..it is sooo good. Yes, they have more than tacos...'taco stand' just means a small 'hole in the wall' place that you walk up to and order. (Did the previous poster that mentioned Santa Monica earlier really mean Santa Barbara? FYI..Santa Monica is near LA.) It's great, but in LA.
We Americans drive a lot so I don't think SF to LA is a big deal at all, but you would need to account for lots of traffic and plan to stay a night or two in LA. If you go, you want to stay in the west side...NOT the east part.
San Diego (IMHO) has the best zoo in the world, and I've been to several, but that is a very long trip. SF to LA is about 6 hrs. (short drive for Americans) if there's NO traffic, and another 3-4 hrs. to San Diego...again if there's NO traffic...and you have a better chance of a major snowstorm in London than experiencing NO traffic in S. CA...anything south of SF is really So CA. Worst case scenario...prob. 8 hrs. to Anaheim (where Disneyland is) and 12 to San Diego. I think Disney World in FL is soooo much better than Disneyland, as the latter is built out with limited space.
Yosemite is wonderful, and you could make a long trip there and back from SF if you didn't have kids, but I'd think you would need accommodations to go there with kids,and it can book out up to a year.
Yes, Trader Joes's is in the Bay area, and also look up Whole Foods...they can accommodate anybody's diet needs, and can probably even give you restaurants that offer gluten-free meals...yes, CA is great.
Also, don't worry about 'family-friendly' in the US, unless you're looking at 5 star places, and even most of them allow kids in the US. Some B&B's don't allow small children, especially if they have antiques or whatever, but most lodging and restaurant choices are not a problem. One of the best places to stay in CA is the Coronado Resort in San Diego and they don't hate kids either. (However, most kids in the US don't run around while they're eating..they sit at the table.) DD gets upset when we don't let her run around in England while she's eating because most of her friends get to...we say you can play before and after you eat, but while eating you will stay seated.
(FYI...some of you might know what I hate most about the UK is that kids are hated.) In addition to the awful NHS, the lack of being allowed to eat good food with children in England is just terrible. However, most of the food is so terrible (not the Indian..it's wonderful) that we don't want to eat out anyway. Sorry, but many Americans do eat too much and the portions can be huge so always ask about portion size as you may want to share...but at least we have lots of choices for different types of healthy, freshly prepared food. Avoid the crap places and go where food is prepared after you place your order and where microwaves are not used, no canned food or little frozen food.
Have fun.