I was in Fiji in 06 and am going back next year for my wedding/honeymoon. It's absolutely beautiful. Here's what I can tell you:
First, understand....it's Fiji. The culture is relaxed and casual. Don't expect the Waldorf Astoria and you'll be fine. Rooms were clean and food was good-don't get me wrong, but understand it's a more relaxed and may not be 5-star by American standards.
Weather: I did my trip in Nov, but a few years before was in Cains Australia in Aug and weather was fine / water was warm.
Fiji Resorts: Garden Island was the best, and we'd been planning our wedding there. However the resort was recently sold to a Japanese company, who has closed it for renovations until Spring 09. When I was there the staff was amazing-I still remember their names and they made me feel like a friend. I've heard stories that the new management is not treating the staff well, thus affecting the overall mood, etc, but I can't confirm that.
I can tell you that it was perfect for what you're looking for. Rooms were clean, great snorkelling right in front of the resort, or off a small island you can kayak to just off the resort. There's no beach at the resort, but plenty of lounge chairs, etc. Beach is on the island I mentioned. Plenty of land based fun-hikes, natural water slide and waterfalls 20 min walk away, lots of fun. Diving is first class and the staff is very professional. Nitrox available if desired.
Pacific Harb: On Viti Levu just across from Beqa island is Pacific Harbor. Aquatrek (who runs the dive outfit on Taveuni) has a set up there (Aqua-Trek). They have an office in San Francisco that can help w/all the bookings. Great staff. They're on site at a large hotel called The Pearl. It was nice, almost a little too fancy for me, and meals were over-priced. However just down the road is a great little resort called Uprising Beach Resort. Nice little bures right on the beach, etc. Diving is good. Aquatrek has a cool shark dive. Land based-hikes, kayaking, river rafting the upper navua gourge is a must (riversfiji.com on site by aquatrek).
Never been to Beqa Island, but heard good things. More secluded than Viti Levu I imagine.
Live Aboards: My personal opinion....live aboards are best suited for hard-core divers who just want to dive. The ones I've been on didn't have much in the way of snorkeling or non-diving activities. I did one out of Cains Australia (Kangaroo Explorer) that was horrible. Food was nasty, dive masters weren't very safe, and I was stuck on that boat for 2 days. Many people swear by live aboards....me, I like to get out, meet locals, explore, etc so I avoid them. If you wanted to, I would suggest more of a cruise ship
I do hope this helps. I have a lot of great memories from Fiji and would happy to share more if you have other questions...just let me know!
1st trip to Fiji and Australia - a few questions.... - ScubaBoard