Murrieta is just north of the San Diego County Line in Riverside County. You are about an hour's drive away from downtown San Diego, 90 minutes with heavy traffic. It's a straight shot down I-15 to CA 163. BTW you will ned a car to get around. Public transportation in Murrieta is slim and none.
You are close to the Zoo's Safari Park, which is outside of Escondido. North County San Diego is home to the Zoo's Safari Park. The annual spring butterfly exhibit is going on now through April. There are also multi acre enclosures where herds of wild animals roam plus lots of hiking trails. It's worth the visit and is a different experience from the zoo. You can ride a zip line, tour the park on a Segway, or take a photo caravan into the enclosures and feed the giraffes.
http://www.sdzsafaripark.org/
San Diego is one of the nicest cities in the country. It's a major tourist destination and there are tons of things to do. With 70 miles of beautiful beaches, countless parks and gardens, major league sports, dozens of golf courses, world class museums, Tony Award winning theater, great cuisine, best weather in the country, high tech industry, major universities, and the best zoo in the world, it's my choice as THE place to live and play in the USA.
Mission and Pacific Beach are your best bet for fun in the sun. Belmont Park has a vintage wooden roller coaster (one of two remaining seaside coasters on the west coast) as well as other rides. There is a strand (boardwalk) that runs the entire 3 mile length of both beaches. It's a great place to walk, run, sun, rent a bike or skates.
http://www.belmontpark.com/
Some must see attractions are the world famous Zoo, Sea World, and Balboa Park. Known as the "Smithsonian of the West" Balboa Park is the largest urban cultural park in the country. You can get a park passport which allows you entry to a dozen museums as well as the zoo.
http://www.balboapark.org/info/passport.php
My favorite museum in the park is the San Diego Model Railroad Museum. It has some of the largest model layouts in the world. It is really awesome and a real hidden gem. Kids get in free.
http://www.sdmrm.org/
Other attractions in the park are the Air and Space Museum, Ruben H. Fleet Science Center and IMAX theater, the Natural History Museum, the Museum of Man, the Automotive Museum, the Old Globe Theatre, the Hall of Champions, the Botanical Gardens, and the largest outdoor pipe organ in the world (free concerts on Sunday).
La Jolla offers great views, great surfing, great food, great theater, and great shopping.
Check out the surfers at historic Windansea Beach. At low tide you can walk out onto the tide pools. Walk along the Cove and check out the caves. Visit the Museum of Contemporary Art. Take a stroll on Prospect St and check out the shops, galleries, and have some authentic Mexican food at Alfonso's. Then head to the Birch Aquarium at The Scripps Institution of Oceanography. It has a spectacular view of the bluffs over the Pacific Ocean. The Tony award winning La Jolla Playhouse is located nearby on the campus of UCSD. For a few laughs at night, The Comedy Store is on Pearl St.
http://aquarium.ucsd.edu/
Take the trolley from Downtown to Old Town. There is a state park there that recreates life in the Mexican and early American periods of 1821 to 1872.
The Old Point Loma Lighthouse at the Cabrillo National Monument offers great views of the downtown skyline, San Diego Harbor and the Pacific Ocean. On a clear day you can see all the way to Mexico. It's a great place to go whale watching as they migrate along the coast.
The USS Midway is an aircraft carrier turned into a museum
http://www.midway.org/
The Maritime Museum offers a hands-on look at San Diego's days as a bustling seaport. You can tour the Star of India, the world's oldest active merchant sailing ship.
For nightlife, the Gaslamp Quarter offers dining, drinking and dancing.
http://www.gaslamp.org/
Check out these sites for discount coupons and other info
http://www.sandiego.org/nav/Visitors
http://thebestplacesinsandiego.com/
If you plan to go to LA you'll head north on I-15 to I-10 west. That communte is a real nightmare and will take a couple of hours.
Los Angeles has all the major tourist traps like Disneyland, Magic Mountain and Universal Studios, but try and take in some sights like the Getty Center. The Getty Center is one of the most impressive architectural achievements in the United States and it also contains some of the finest works of art in the world. Because if it's large endowment, it's free. The museum also offers spectacular views of Los Angeles on clear days. It also has one of the best restaurants in LA
http://www.getty.edu/index.html