Myself, I've lived in the San Gabriel Valley for a great part of my life - we're slowly being boxed in by the liberals who've taken Pasadena and Claremont, but the cities inbetween are for the most part reasonable. Most of the Central Valley upstate is ok, just in a horrible economic depression.
Orange County is so-so - costs are enough that I'd consider moving just about anywhere else first. And I hate to say it, but same goes for most of North County of San Diego.
Alas, if she's wanting to avoid ‘redneck mentality’ it does cut down options. Valencia/Saugus/Canyon Country are borderline. The sane areas of Riverside County are redneck central, same with quite a bit of the central valley. Victorville region would probably also be borderline.
All in all, based on your comments, your best bets are: eastern San Gabriel Valley, Orange County, Canyon Country, Hidden Hills/Reseda.
I’ve heard Temecula and Murietta are nice. Any opinion?
Um, not Reseda.... Unless she likes home invasions and speaks a pretty fluent Spanish.