I would be on the island with and endless supply of Noro's Kureyon. I wouls also need some packing stuff from FedEX to pu and take away the scarves, hats, and sweaters that I had been producing. I never get tired of the varigations or the subtle changes in colorways.
I would want to be there with the book 25 Last Minute Knitted Gifts because there is so much variety in it. And, I would probably want cashmere. I mean, if I'm going to be stranded (pardon the pun), I want what I consider the softest best yarn.