We flew into John Wayne airport (Santa Ana/Orange County) last fall and are flying there again in January. Seems to me it was a few bucks more to fly into there than LAX, but the transfers were cheaper because it's closer, so it was pretty much a wash. It was a very easy airport to navigate.
SNA is definitely the preferred airport by most Disers.
Long Beach and Ontario are other options. Long Beach is about the same distance as SNA, but Ontario is quite a bit further and would require a car rental.
I always fly Southwest into SNA. I tried Jet Blue one time and flew into Long Beach. I loved Jet Blue and the Long Beach airport was nice... very small and easy to manage but it cost quite a bit more to get to DLR than from SNA. I'll pay a few bucks more to fly into SNA just because it's so close and it's only $10.00 for a shuttle to DLR!
It all depends on cost of airfare, and how you want to get to disneyland, rental car, conivence to get to rental cars, some airports do not have car rental desk in the terminals, to me it is a pain to be shuttled to One company and it can take much longer. The cost of Shuttles? The cost of a Taxi?
We arrived in Orange County (John Wayne, SNA) and it was great!!!! Not a super big airport, but very nice we will use it again. It was only about a 10min drive to Disney, I think we took the 55 to the 5 and the signs lead you right to Disneyland DR.
We have flown into LAX and John Wayne and prefer John Wayne hands down. It is a very nice, small airport and easily navigated. LAX is big and the lines can be confusing along with the security lines - ick!!! The security line at John Wayne was non-existant. (So nice!) We travel from DIA in Denver so we are used to having to stand in lines, but at John Wayne, there aren't any!!! Have I convinced you yet?
I always prefer to fly in/out of SNA/John Wayne and Long Beach. They're smaller airports, and it makes getting in and out much quicker. Plus, they're closer!
When I lived in N. California, we flew from SJC to SNA (when we were not driving), but now that I am in Colorado, it was MUCH cheaper for us to fly into LAX from COS. We are renting a car anyway, so that was not a factor.