While living on the West Coast makes WDW a pain, it pays when it comes to Hawaii trips-we've gone 6 or 7 times. Once we had to pay $800 pp, over Christmas, but it's not uncommon for us to go for half that or less. Might be worth getting cheap airfare from the West Coast (there are often sales in the summer) then just getting yourself to the West Coast separately. You could always spend a day or two at DL
. Recently, AK Airlines had $169 each way to Hawaii.
Definitely, get a car. I would skip the very expensive looking Aulani excursions and just do your research and go out on your own. It's a very small island and it's very easy to find your way around. My understanding is that the area Aulani is is windy, and won't be great for things like snorkeling. Drive around down south to snorkel, go learn to surf on Waikiki.
Stop at the Costco first thing and stock up on groceries. Cheapest place on the islands to buy groceries; prices are pretty similar to mainland prices.
When we go to Hawaii (and we usually go to Maui; I much prefer it to Oahu, though Aulani looks gorgeous) we take it very easy; I'm a commando visitor at Disney, but in Hawaii we often have nothing scheduled for days at a time. Get up early, sit on the balcony and drink coffee, swim in the pool, hit the beach in the morning before it gets windy...drive around a little.
We liked the Polynesian Cultural Center, watching the surfing competition at the North Shore, and snorkeling. Honolulu was interesting for a day or two, but a little overstimulating for how I want to spend my time in Hawaii. A visit to the Arizona is a must, I think.
