1 Island or 2 in 7 days

You could do all of those activities on Kauai, so my vote is to stay on Kauai for 7 nights (but Kauai and the Big Island are my favorite islands!)

Our family of five once spent a whole week on Kauai (our second visit) and we never ran out of things to do.

Kauai is much less touristy than Oahu, so if you're wanting more nightlife, lots of shopping, etc., I would recommend Oahu.

I'd suggest one unless you fly into Oahu and spend the night to see Pearl Harbor (a must). However, you lose 1/2 day (easy) when traveling between islands.

For 7 days, I'd also suggest one island. There's so much to do on each island, no need to spend precious vacation time traveling to the next island. We love Kauai and the Big Island.

With only a week, I'd pick only one island.

I would do four or five nights Kauai, then two or three on Oahu. It will be wonderful, whatever you do. I actually enjoy the interisland flights (views divine) so I don't consider that time wasted!

I'd suggest a couple of days on Oahu to take in the sites and then off to Kauai for ziplining, snorkeling, boating and flying.

Kauai is my favorite island as it is less commerical and just beautiful.

I don' think you can go wrong on any of the islands but with one week you will not see it all...even if you are on one island the entire time.

4 or 5 days on Oahu.

2 or 3 days on Kauai.

there is much more to see & do on Oahu than any other island.

Lots of info including sites with free brochures for all islands:

http://www.fodors.com/forums/threadselect.jsp?fid=1&tid=34812564

I agree with Dusty. If this is a once in a life time chance to come to the Hawaiian Islands, do both. Stay longer on Oahu. But if you decide to just do one island you will still have an amazing time. Happy Travels.

As you can see it's a tough choice for many including ourselves on our first visit.
It looks like a fairly active group as a whole so I'll go along with Dusty also.
The time of year comes into play possibly too for Napali Coast cruises on Kauai would it not?
Pearl Harbor and the Punchbowl may have more meaning to the 65 couple but even the 9 year old should enjoy the tour of the USS Missouri.
A trip to Dillingham airfield for a sailplane ride or skydiving on the northshore is an option.

oops, forgot to say, for me personally my "only one island" would be Oahu

Our group has read all the most helpful comments and have decided that we must do a couple of days in Oahu. While we agree on Oahu, we're wondering if the second might be the BI or Maui instead of Kauai. Your comments would be welcomed.

If you want two, yes I would choose Maui as your second. Mostly because of all the organized activities you mentioned wanting to do.

Now you did it this board will probably implode with all the opinions to come.
You may want to do more research on the other islands and pickup some of the guide books.
We're going to spend a few nights on the BI for a couple of reasons one being it has an active volcano and we "may" get to see a lava flow.
The other is we found an oceanfront place we could afford and of the four main islands it's the only one we haven't spent more than a day on.

Since some of your group is interested in the Big Island, I'll mention a few of my favorites places. This would be an excellent place to take your helicopter tour. Going over the volcano is breathtaking.

The Big Island has 13 of the world's 15 climate zones, and the world's tallest mountain, Mauna Kea. It is larger than all the islands put together, and less populated than the other major islands. It is a very special place, and as are all the other islands, it is stunningly beautiful.

Some activities your 9 year old might enjoy are the Sea Horse Breeding Center, horseback riding in Waimea (the original Cowboy/Paniolo country), seeing ancient Hawaiian villages Lapakahi, and Place of Refuge, as well as the Pu'ukohola Heiau near Kawaihae (where Waterworld was filmed).

The small towns of Hawi and Kapa'au, the birthplace and childhood home of King Kamehameha are so beautiful, and have many talented artists and musicians who live there and share their craft with the close community.

There is a 6 hole golf learning center in Kapa'au where anyone can play for $6. Children are $3.25 and free on Mondays.

There is an interesting Tsunami Museum in Hilo, and many amazing gardens, especially the Hawaiian Tropical Gardens, and waterfalls you can hike to (Akaka Falls and others).

The helicopter rides out of Hilo are less expensive, but the deluxe one out of Waikoloa is quite special. (Blue Hawaiian).

Hilton Waikoloa Village has a Dolphin Quest Program (you learn about and swim with the dolphins), and the hotel itself has a monorail and boat ride. It's quite fun for a 9 year old, and it is sometimes rather affordable.

South Point is the southernmost place in the U.S., and there are green and black sand beaches.

There is an Macadamia Nut Factory (Mauna Loa) with free tastings, and a zoo with an albino tiger. The Hawaiian Vanilla Company is the only place in the U.S. that grows vanilla, and they have dinners and tastings.

Mauna Kea observatory is quite interesting (I haven't been myself).

Kona has lots of shopping, a palace and very old church. It has a big new outdoor shopping center/flea market that is fun for souvenirs. All the activities are available in Kona as well, and the Fairwinds is a wonderful snorkeling boat in Kealakakua Bay, where you will see dolphins at play.

All the resorts allow you to visit for shopping or a drink, and all the beaches are public access. The Mauna Lani is my favorite. There are several new shopping centers at the resorts.

Well, my point is you will love the Big Island, and there is so much to do there. It's big though!

While the Big Island is great, and I would love to go back maybe next year, it is very big and takes a week or more to see most of it.

Personally we prefer Kauai over Maui, Kauai is definitely the place to do the helicopter ride and the Na Pali coast boat trips are terrific (but in November you may have to go out of the Southwest shore). Also in November it may or may not be too rough for those Zodiacs, they are also tough on anyone with a bad back, which is why I have never done one, but you may get lucky with the weather and have a ball.

Wherever you go, have a great trip.