I agree. You need to supply more info, including where you will stay, what you want to see, how much time you will have total, whether the cost of car rental and parking is a problem for you, etc. I utilized trollery (light rail) and busses to get around while we were staying in the convention area, since parking fees at our hotel were $25-30 per night. To places downtown, and even Balboa Park, it was fairly easy (I walked to the USS Midway). To the Scripps Aquarium in La Jolla, a bit of a pain. If I had wanted to go to the Wild Animal Park, it would have been impossible without a car, UNLESS I took a tour (which is another option). Of course, if you're staying in, say, Hotel Circle or La Jolla, you pretty much need a car (and parking at your hotel may well be free).