San Diego - and zoo - are worthwhile if you have time which is precious on such visit. It's two and a half hours one way if you miss rush hour though and who wants to sit in a car for best part of a day?
Within Los Angeles, I agree the Getty Museum is a good visit as is the Queen Mary, now a floating museum moored at Long Beach. I'd also put in a word for the Griffith Observatory and Planetarium, the most visited attraction of its kind in the world. It's located on the southern slope of Mount Hollywood in Griffith Park, and is the best vantage point for observing the world-famous Hollywood Sign.
http://www.griffithobservatory.org/a...servatory.html
and of particular note to ourselves, the Observatory and Griffith Park were donated to Los Angeles by the bequest of Griffith J Griffith 1850 - 1919, a Welshman born in Bettws who made his money as a mining consultant on the west coast. A colourful character, Griffith
later spent 2 years in jail after an attempt to kill his wife. He also donated 3,000 acres of land to LA which to this day is known as Griffith Park. Wiki bio here:
https://en.wikipedia.org/wiki/Griffith_J._Griffith