There are two "villages", Avatoru and Tiputa, both located on the very narrow inhabited zone in the Northern area of the atoll. Avatoru is on the same motu as the airport, however you will need to take a boat to get to Tiputa.
French is the official language, and Tahitian is also spoken, but the majority of tourist-related activities will be able to cater to English speakers.
Air Tahiti flies into Rangiroa from various Polynesia islands such as Bora Bora, Papeete, Fakarava etc. Rangiroa Airport is located at the main motu of Avatoru, near the village and near most hotels and pensions. The airport has an Air Tahiti agency, snack bar, souvenir boutique and public restrooms.
Most travellers stay at Avatoru motu (Tiputa motu is only accessible by boat). Not much point renting a car, it is probably best to hire a bicycle, there is only one main road on Avatoru after all, and it is just a few kilometers long!
You will need someone with a boat to bring you to the outer motus.
Silvertip (and sometimes hammerhead) sharks can be found in the Avatoru Pass dive site.
Tiputa Pass is great for reef sharks (and also possibly hammerhead), dolphins (sometimes they come and play with you!), eagle rays, manta rays, barracudas, tunas, and many other smaller colourful fishes!
On the boat ride to and from dive sites at Tiputa Pass, you might even see dolphins jumping out of the water playing with the waves.
Scuba Diving is breathtakingly fabulous in and around the Tiputa pass, with dolphins, sharks, manta rays, turtles... Coral and "small animals" lovers may be disapointed, but for the "big thrills", Rangiroa delivers. The drift dive riding the current flowing from or to the lagoon through the pass is an absolute must-do. Drift snorkeling is a great adventure. At any time there are manta rays that go through the pass.
The tour to the Blue Lagoon is also a great trip. It takes about an hour from the Kia Ora to get to it, but is an amazing sight. There is not much in the way of coral to see, but there were plenty of blacktip reef sharks (over 40) when we were there. Most of the sharks are small, but it is quite an experience when you are not expecting them.
There are only a handful of places where you can grab something to eat on the island. Do not expect 5-star gourmet food, however you can give a try a the following places:
Like other similar small and sleepy atolls of the Toamutos, there is no night life. The locals maximise the sunshine hours by getting up before 6am and retiring early when the sun has set.
There are only two "large" hotels, the luxurious Kia Ora and the confortable Novotel. Besides those hotels, there are several smaller family-run pensions, for instance Les Relais de Josephine.
One of the cheapest family-run pensions would be Pension Loyna (http://membres.lycos.fr/pensionloyna/us/main-us.htm). Loyna is very friendly and helpful, provides free bicycle rental, knows everyone else in the island, and cooks delicious meals!
Although there are (plenty of) sharks in the area, some of which often come very close to the shore, they are for the most part harmless.
Rangiroa, French Polynesia: Pension Bounty www.pension-bounty.com
Tikehau is only a few km away on the map, but counting taking off and landing, it takes 20 minutes to get from Rangiroa to its closest Tuamotu neighbor.