If that's the case, Millbrae is a great stop. It has good schools, a safe downtown with many local shops, and a library. These are all within walking distance of the BART station. As an added bonus the station is the only station that also houses the Caltrain.

The only draw back is that a ride to/from say, the Embarcadero can be fairly long at times, sometimes approaching 45 mins off peak. Yes, I know it's only supposed to be 35 mins, but from my experience it's always a bit longer.