You probably should not plan on taking the Pacific Coast Highway all the way from San Franciso to SoCal. It is very slow going. It is beautiful, and worth seeing, but you will probably want to do a chunk of your drive inland. Staying on either side of Big Sir (or both) is a good idea. Monterey has my favorite children's park. I went there as a kid and still go back everytime I go (now taking nephews and next time my own kids). It is the Denise the Menace Park. Very cool.