Zoo for sure. We have the best.
Zoo or Safari Park. Zoo has a baby hippo which might be on display when you visit along with a huge, brand-new penguin exhibit, Safari park has baby tigers in the nursery and grown tigers in the forest. Plan most of a full day for either park, the zoo is huge! And wear good shoes, lots of hills in both. Food varies, avoid the Italian place at the zoo, but the place over by the elephants is tasty. Or if you want something more filling, Alberts restaurant is a table service place with great food (but pricey). Zoo has free parking, Safari park you have to pay. In either case, remember that animals sleep during the heat of the day (afternoon), so get there as close to opening as possible to see the most animals. If you don't have a car, then the zoo is probably your best bet.
I love both. San Diego has the best.
Bring your walking shoes!
The zoo is definitely the better bargain