I ate sashimi the whole time I was pregnant. I'm on the west coast, and in my province, there has never been an incident of sushi-borne listeria. It's more important to limit fish with high mercury levels (like tuna and shark.) Avoiding raw fish is no longer an official recommendation. A bigger issue are things like salad bars, and a few doctors have now started telling patients to avoid organic while pregnant since the rate of contamination is so much higher than with conventional produce.
As far as
Disneyland-specific food choices, other than alcohol, I can't think of anything. Hamburgers should be fully cooked. Maybe avoid buffet-style restaurants if only because with other patrons you're relying on them not touching your food. Even then, the absolute risk is quite low. The food and water supply in North America is incredibly safe on the whole.
You're not due for a pertussis vaccination until your third trimester. My biggest precaution would be checking your titres to make sure you still have immunity to measles and rubella, if you didn't pre-pregnancy, because you have so many visitors from all over the world at Disneyland, and that area of California has one of the lowest vaccination rates in the country.