You can be in North County San Diego (Oceanside, La Jolla, Del Mar) in less than two hours from where you are. Good sightseeing and there are the beaches (a little cold this time of year, but they are still fun). Go a little further south and you can hit Old Town San Diego which can be fun for kids, or even hit the Wild Animal Park in Escondido or the Zoo in Balboa Park. Head north and there is the Long Beach Aquarium (buy tickets online at their website, its cheaper). If you have chains with you or a 4wd you could head on up to Big Bear or Lake Arrowhead. Huntington Beach and Newport are right down the street from you. Irvine Spectrum is really just a big outdoor mall but they have a ferris wheel. Ummm...I'm running out of ideas, give me a few hours and I'll get back to you haha.