There are two airports in the area that I recommend. One is LAX which is Los Angeles.  The other is SNA which is in Orange County.  Depending on where you are coming from I would suggest you check out both on the rates.  Sometimes one is higher than the other and vice versa.  SNA is much smaller airport and you are in and out fairly quick.  I suggest you eat before you go to the SNA airport.  Not a lot of food at this one in my opinion.  It is a nice, clean and easy to get around place, but very few eating places that fit my needs.  There is a Mexican food place across the street from the airport that I tend to go to before I leave town.  LAX is  much bigger and takes a little longer to get around.  You for sure want to leave 4 hours prior to your flight from Laguna Beach.  You may even want to leave 5 hours just to be on the safe side in case traffic is bad.  SNA I suggest 2 and half hours if it is not rush hour.  The only thing you have to watch out for on leaving any of these places is weekend events that bring lots of people to town.  I went for a UFC Fight and the lines were really long on the Sunday that I left.  I made the flight with no problem, but the check in time was much longer.  Rental car return is real easy at both airports, but especially fast at SNA.