We stayed at the Doubletree Club in San Diego (Hotel Circle). We got a family suite (a hotel room with a king bed and a separate room with a bunkbed for the kids). I booked the hotel on hotels.com (going through ebates for 3% back) and I sent in my rebate for $20 for staying at least 3 nights.
We saved money by eating breakfast in our room. I brought a box of cereal, some hostess donuts, some muffins that I made, and I bought some milk and juice when we got down there. One morning we went to my in-laws and ate breakfast there. We used paper cups, plates, and utensils.
We didn't eat out very much, except for when we were on the road. We were lucky to have lunches and dinners with family and friends most of the time. Otherwise, we ate some snacks that I had packed and/or bought when we got into town.
When we did order out, if I could split the kids' meals, I did. This kept the cost down. Those kids' meals are expensive! In fact, the morning we drove home, we stopped at McDonald's for breakfast. I ordered one order of pancakes, which had three pancakes: one for each girl. : )
One thing that helped keep our kids (and us!) sane on this trip was the Disney Songs and Story CD's. They have 5 songs from a Disney movie and then a narration of the story (about 10 to 15 minutes). It really kept my kids' attention. We didn't use videos, which I was really happy about, too. The CD's come in lots of the Disney movies and you can get them on Amazon or half.com (which is where I bought mine).