Old Town Orange

Old Town Orange is essentially the beginning of Orange County, and it's heart. Most of the buildings were built between 1888 and 1940, making it one of the older cities in California. For this reason movies such as Fallen Angel, Gumball Rally, Gentleman's Club, Big Mama's House, That Thing You Do, Adventures of Rocky and Bullwinkle, The Last Dance, and more have all had scenes in or around the Orange Circle in Old Town Orange.

When in the area, Old Town Orange is a great place to visit, it has some great food including Felix's Cafe (Cuban food) and Watson's Drug & Soda (good for a sandwich at lunch).  Old Town Orange is also known for its shopping, mainly Antique shops, if that's what you're in to.  By night the area changes over and becomes an active bar zone, with bars such as District Lounge, Pauls, and O'haras.

The largest mall in California - South Coast Plaza

Orange County is a shopper's mecha if you know where to go.  South Coast plaza is the biggest mall in California, and with sales of over 1.5 billion dollars annually, it rakes in the most cash of any mall in the United States.  South Coast Plaza has over 250 retailers and 30 restaurants, and the area around the mall has a lot more shopping as well.  If you're looking for a luxurious, high end mall, with all the top brands, and world class boutique stores, this is your mall.

From the website:
South Coast Plaza defines the luxury shopping experience with extraordinary boutiques, personal shopping service, and upscale amenities all within a short distance of the world's most magnificent vacation resorts. South Coast Plaza is recognized internationally for its unparalleled retail collection and award-winning restaurants.