My husband and I want to go to Hawaii this summer for one week. We have never been. I don't know one island from another, but we want to splurge on a really nice luxury hotel...do water sports and also hike. Any recommendations for island/hotels?

This is probably THE most frequently asked question at this forum. I will wager there are well over 1000 opinions about this in the archives.
Have you done any reading?
The answers are always pretty much the same.

There are thousands of options. For my experience we went to 3 islands, Oahu , Maui , AND Kauai. For only one week i would go to Oahu for 2 nights and stay on the beach, to get the feel of Hawaii. Then i would take the island flight to Maui for 5 nights , and book the hyatt in kaanapalli. There are many activities on Maui. Do a search for activities in hawaii or maui and pick what would you like to do. I used activity warehouse to book all my activities, like snorkle trips dinner sailings,luaus, and whale watch trips. And in complete agreement with ( travleis ) read all the back posts for more information. nick

Maui is my choice, and why stay in a hotel room, when you can rent a condo and have the comfort and space of home. We stayed at the Kannapoli Alii and it was fabulous. Our unit was on the top (11) floor with views to die for. The pool and grounds were spotless, and if it's ocean/beach you prefer, Kaanapali beach is the best. We especially appreciated the helpers who handed you a large fluffy beach towel and carried a beach chair to where ever you wanted to set up on the water. All of the help were the greatest and so helpful. It was our greatest vacation ever. The gas grills and covered eating area were also a nice change of pace from eating out every night.

The Princeville Resort in Kauai has what you're looking for
http://www.princeville.com/stay/index.html

The Sheraton Maui is wonderful.

The Hyatt Regency on Kauai is wonderful. Both islands are great and have differences that make me suggest you visit both. If you have time, a night on Oahu would be great to see Pearle Harbor. It's a very emotional place to visit.

Here is my two cents:

Maui-Ritz Carlton Kapalua or Four Seasons Wailea

Oahu-The Halukulani, the W Honolulu and the Kahala Mandarin Hotel

Big Island- Four Seasons, Fairmont Orchid or the Mauna Kea or Hapuna Prince.

Kauai- Hyatt or Princeville Resort