If your idea of a good vacation means being near the water, make a beeline for Naisoso Island. Whatever you choose to do here, you're unlikely to get bored of those pretty views.
If you're making your way to Naisoso Island in Nadi, make sure you leave time for some other sights too. After you've finished at this water-surrounded land mass, Port Denarau Marina isn't too far away and will keep you going for a bit longer.