I've lived in orange County a great part of my life and have lived other places both in California and out and can offer a comparision for those wanting to know about the area.
First off, I hate Irvine. It is devoid of all culture and character. It's the safest city in America, but at the cost of losing anything that would make the city interesting. The one lone spot is the artsy theatre across the street from UCI that we go see indie movies at occasionally. Plus, Irvine is so expensive, you won't be able to find anything resonable in Irvine. But I have heard from people I know going to school that the married housing is nice. UCI's campus is actually pretty nice.
But don't let Irvine tarnish your thoughts about Orange County as a whole. It's a great place to live with plenty of things to do, both culturally and actively. The beach is 10 minutes away. There are plenty of record shops and movie theatres. But with all that, a car is a must. There's no way around it; if you want to do stuff, you need a car.
I recommend Costa Mesa.(My hometown.) It's close to Irvine, without that icky Irvine feel to it. It's home to South Coast Rep (the best theatre west of Broadway), OC Performing Arts Center, and a burgeoning art community. Plus, it's way cheaper than the surrounding cities. (Newport, Huntington, Irvine.)
Hope this helps.