We go to Disneyland almost once a year. I know you said you don't plan on going anywhere else. I would say rent a car, the reason for this is that you could go to walmart the first day and get snacks (which you can take into the park). There's lots of options for food outside the park but it does add up, if you eat inside the park or outside. Plus you can go to other places that's not close to the park. We normally take jetBlue and fly into LGB, which we just take back roads to the park.