Been to Aulani twice. Here's what I've learned and where we went:
North Shore: Dole Pineapple Plantation and Matsumoto Famous Shaved Ice
Pearl Harbor: Get there VERY early before tour buses and take into consideration the traffic from Aulani to HNL (it's pretty bad).
Leonards Bakery: HNL. Parking is horrible. Lines can be long but worth the trip. We went twice!
National Memorial Cemetary: Beautiful. It was a special trip there for me, I have an uncle buried there. I found the site quickly and easily and placed flowers.
Hanks Haute: Saw this on Diner, Drive-ins and Dives. Best crème brulee I ever had. I know....hard to believe.
I thought trying to get a "deal" on a rental car was kinda difficult. If I recall, I think it was about $400 for one week. When arriving in HNL and heading to Aulani, look for the shopping center where Target, Costco, Safeway and many other stores and restaurants are. It's on the opposite side of driving when heading to Aulani. That's where everyone goes for food and other necessities. Many, many people leave the hotel at night for dinner. Whether they go across the street or to Roys down the road or into HNL. Many do not find the food at Aulani very good, and it's very expensive.
Have a wonderful trip.