we went to the shangri la on the main island (coral coast). Great for kids with a kids club. It has a really nice lagoon for snorkelling and also sailing.
The wind came in from the south east every day around 15+knots in February. The resort has surf cats we would use for sailing. Flat water only. I guess you could windsurf there as well, no one else was though. Nice resort though.
There is a reef break for surfing on the high tide they will take you out to for a fee.

I stayed at Castaway Resort a few years ago. Good kids club. It sits on the edge of the wind line. All flat water unless you want to go out about 1/2 kilometre to the reefs. I just used the resorts Catamaran and a big Starboard floater. There was a Kite guy staying there and he sailed straight off the beach each day. I have also stayed at Plantation Resort. It has a good kids club. It sits in a wind shadow so you would either have to get taken out by boat to "sand bars" about a kilometre away, where the kite guys sail, or perhaps carry you gear up the beach 300 metres to the point where the wind starts. If you want to stay on the mainland, Denarau Island is okay in front of the Sheraton. I guess they have a kids club but I have not stayed there. It is directly onshore and the water is not pristine like the islands, but okay. Hope that helps. Gary Coffs

Don't you just hate those "non windsurfing friend" recommendations.