VACATIONS IN OC (Orange County)

Ciao OC InterNations friends,
Two Italian Ladies visiting California in the second half of August. We are planning to spend 5/7 days in the OC and we are wondering if you could give us any suggestions in terms of MUST to be visited and NICE to be visited locations in the areas and may be also some tips about accommodations (We are looking for something not too much expensive, but clean and with warm water)
Many thanks in advance for any feedback :)