As long as you get yourself a grass skirt, then all bases will be covered.

You should go bother Papa...he grew up in Oahu!

Wow, that's hardcore! Well J, I grew up on Oahu, so I can try to give you some tips.

Definitely hit the beaches and definitely hit the beaches outside of Waikiki (Waikiki is fine too though, you staying there?). Once you get out to the Windward side of the island and the North Shore, on a weekday you'll have many beaches to yourself. Lanikai is a beautiful beach.

Lotsa people love to hate Hanauma Bay, but I'd hit it. Just go early in the morning. It's a marine sanctuary in a half blown out crater. Lotsa fish to see.

Some awesome places to hike too (and get that "lost" experience).

There are a lot of Lost location shots from flashback scenes that are in town that might be interesting. There's a canal and bridge that gets used in almost every Sun/Jin flashback in Chinatown (along River Street). But I'm sure you're savvy to all that stuff.

A lot of dudes do the parasailing thing: link

Kite-surfing is taking off too. I always see a lot of kite-surfers out in Waimanalo when I'm in Hawaii (windward side):
link

And ocean kayaking is awesome. There's a really nice spot out in Kaneohe to go kayaking where you can hit all these sandbars little lagoons and the like.

Oh, and a guide book recommendation:
link

These books have cheesey covers and kinda cheesey production value but the content is really good. Even as a former "local", I find the info in them of high quality. Very frank reviews. If something is crap, they'll tell you.

There's other stuff that folks go to see: The Arizona Memorial (WW2), the Dole Pineapple Fields, The Bishop Museum (Polynesian stuff), etc. But at the end of the day, a trip to Hawaii is all about kicking back, chilling out and hanging out at the beach. Oh, and wearing as little clothing as possible. T-shirt, shorts and slippers (flip flops) can get you into most restaurants :-)

I can give you more pointers if you need em. But you've got some time to plan.

I trust I am still coming with? ¬_¬

Of course, how would I carry all my stuff else? Rephrase that, how would you carry all my stuff else.