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@mattchu758 said, traffic can be horrible here. Aulani is on the west side of the island with access to H1, the main highway that leads into Honolulu. In the mornings, starting as early as 4:40am, traffic can back up for miles just getting to the junction with H2 (which leads to the North). H1 then becomes a large, slow-moving mess that crawls toward Honolulu, which improves about 8:30. Starting about 4pm, traffic can start slowing down or backing up on H1 coming out of town as traffic once again crawls toward the west and north. This mess lasts until about 7pm or later. It is somewhat better when school is out. But, there's a rail system going in and always pothole patching, which causes even more havoc.
If you head north, on H2, you'll run into Kamehameha Hwy, which runs along the North Shore. Actually, it circles the island (except the west part) and is a very cool drive. Since it is a 2 lane road along the North Shore, traffic tends to go slowly because of many people stopping to look, to park, etc.
If you want to see Oahu, I'd recommend going via the North Shore one morning to see the beaches. The Polynesian Cultural Center is in Laie, and is well worth going to. It opens at noon (I think) and has representative villages and shows of various Pacific island nations. There's a buffet at night and a terrific, well-done show in the evening. It lets out about 9:30 or 10pm. If you drive, the easiest way back to Aulani is the way you came, via North Shore Kam Hwy, H2, then H1 to Aulani. This would be a full day's touring.
The other end of the island has some very nice things to see, which would be another day outing. Take H1 through Honolulu, stop at Diamond Head, Blow Hole, etc. Hanama Bay is great for snorkeling, but hard to get into since the number of guests allowed in is limited. Lots of nice beaches, too.
Before Honolulu is the USS Missouri/ Pearl Harbor area. If you want take the boat out to PH memorial, get there early because the tickets go fast when the tour buses pull up when it opens. you buy tickets for the USS MO, the Bowfin sub, and Pac Air Museum at the PH complex just off Kam Hwy. Again, the rail is being built along that road, so traffic is a mess.
People hear of Waikiki Beach, but honestly, it is not worth fighting the traffic, etc to see it if you aren't staying down there. Crowded, with lots of shopping and tourists, and the beach is nowhere near the prettiest on the island. Aulani is on the west coast of the island, which is not really a place for tourists (or most locals) to wander. If you want to drive to the end of the road on the west coast, you'll see lovely views, but my advice to friends visiting is to stay in your car. If you want to visit an outlet mall, stop by Waikele Outlets and mall complex, which is about 20 min from Aulani off of H1. Outlets on one side of the road, Kmart and a few more on the other with a tram between the 2. The area is beautiful and the lower shopping area has a beautiful view of Pearl Harbor and all the way to Diamond Head.
Drive or take a tour? Driving gives you more freedom, especially if you have a lot you want to see. But, do plan your outings so you won't get caught in traffic and miss a dinner or show at the resort. With a tour, you can sit back, enjoy the view, read, etc while in traffic. If you don't have a long list of must-see places, I'd recommend looking into a day tour that includes the North Shore in the morning and Polynesian Cultural Center visit, dinner, and show in the evening.
Other questions?, Just ask and I'll do my best to answer.