Yes, Fullerton is definitely part of Orange County. On the margin, but squarely inside.
I've tried Fuoco and Ortica, and Fuoco wins between those two. I still have to try Settebello and the one in Laguna Beach, I forget the name. Would you say that Cucina Enoteca is Neapolitan? What other NP places are out there in the OC. Another one that I just love, although it's not Neapolitan, is Pitfire in Costa Mesa. Their pizzas are really fantastic. I was just there last week and it was really good.