Define best. Do you care more about price, stops, schedule, connecting airports, what airline you fly? There are tons of airlines that fly from the west coast to Manila. If you haven't already, just plug in some dates that you can search now, either similar dates this December to account for possible seasonal flights (but same days of week you might travel), or the closest you can get to your trip at this point, and you'll get an idea.
Philippines Air is certainly your most likely choice for a non-stop. And their prices tend to be pretty good, especially if you catch one of their fare sales. It won't always be the best price though. Non-stop has many things going for it, but a reasonable length stop or connection to stretch your legs on a long trip isn't always a bad thing either.
I find that when I consider the times of connecting flights on each end that will automatically rule out a lot of the options, especially since I'm coming from the East coast. You probably don't have that issue as much being near the West coast and presumably taking a bus or something to Anilao. But you may not want to leave your house at o'dark hundred if you don't have to. Or arrive/depart Manila at weird times that are bad timing for the Anilao transfers. Or maybe you decide you'd actually prefer to crash in a Manila hotel for the night before continuing on to Anilao. Or whatever, just play with it a little someplace like kayak.com where it's easy to narrow down the choices, and you'll quickly have some opinions on your better options. (If you did have a connecting flight in the Philippines, I've also found it's worth at least considering considering what terminals they use, and trying to stick in the same terminal if possible. Getting around MNL seems to be getting a little better, but you still have to assume it will suck, and you want plenty of time. In your case where does your ride to Anilao leave from, and when, and how do you get there?)
Our most recent trip we did United/All Nippon with a reasonable connection in Japan each way. The Tokyo airports are quite nice. You could similarly do American/Japan Airlines. And Cathay seems like a good option. Another trip we did United with a stopover in Palau. We've also taken Philippines Air, which was fine. I would also probably skip the Chinese airlines.
