Maybe it's because I live in San Diego and have driven that way many times, but a tour of Orange County just doesn't grab me. OC is the most populous county for it's size in the entire country and has some of the worst traffic.
If it's been a few years since you've been to the San Diego Zoo, you probably wouldn't recognize it. There has been a lot of construction in the past few years, including a brand new elephant area. It only gets better...