People often ask me where they should go in the South Pacific. Lacking the ability to read minds, I do not have an easy answer. In other words, it depends on what you want to see and do on your own vacation. What I can do is give you the benefit of my expertise so that you don't waste your valuable vacation time.
If you live in the United States, Canada, the U.K. or Europe, the long flights here and back mean you will burn a day getting here and a day returning home. Consequently, you should spend more than 1 week out here. If I had only 1 week, I would spend it in one island country, or even on one island. (Also I would pick only one if my primary goal is to spend as much time as possible in the water.) I suggest itineraries that will do some degree of justice to the Cook Islands, the Samoas, and Tonga, which are smaller than Fiji and French Polynesia. I recommend 2 weeks for either of the latter.
The vast distances and the infrequent -- in some cases nonexistent -- air services between the islands make it difficult to see more than one or two South Pacific island countries in less than 3 weeks. You can see Samoa and Tonga in 2 weeks using Air New Zealand's weekly flights, which stop in both on their way between Auckland and Los Angeles. Air Pacific flies at least twice a week from Fiji to both Samoa and Tonga, but not between them, and Air Tahiti connects Papeete and Rarotonga in the Cook Islands. There are no other east-west flights among the islands.
However you construct your own itinerary, first find out the airlines' schedules and book all domestic inter-island flights well in advance. Do not wait until you arrive in the islands to take care of this important chore.
And remember the old travel agent's rule: Never stay at the most luxurious property first. In other words, anything after that will seem inferior, and you may come home disappointed.
Note: This information was accurate when it was published, but can change without notice. Please be sure to confirm all rates and details directly with the companies in question before planning your trip.