Long Beach State and Cal State Fullerton would be on my list.
I had a project in Orange County for two years and we stayed in a Marriott on Cal State Fullerton's Campus. That university is about 25 miles inland from the ocean, and it's on a plot of land about the size of 5 city blocks. The baseball field is open year round for things like high school practice. Good baseball team historically, but not exactly a great place to be. As far as the student body goes, it's very commuter.
Re: Pepperdine. I've been out to that campus many times, but I'm not sure how great the nightlife is going to be in Malibu.
It pains me to say this, but if I were going to go to school on the West Coast I'd pick UCLA. Big school, you're right next to Beverly Hills, and you're close to the beach. Westwood feels like a small college town, but it's in the middle of LA.