We ate very well at the Sheraton. After being on a remote island for a few days we were just glad to have chicken that was refridgerated. I bet the Sheraton could arrange a driver for you. Enjoy your time there! If you get desperate you can always eat at McDonalds!!
I found this suggestion on another site:
Vilisite's is the first Fijian owned restaurant in the country and has a great relaxed atmosphere. You eat on the deck facing the ocean in a quiet area of the Coral Coast. A three course meal starts at about F$20.