If there's concern over the newbies getting a cab I would recommend setting up a private taxi in advance. I can personally recommend Rachel - 340-771-2986. There is no better smiling face to have awaiting your arrival. She'll meet them at the airport and whisk them to whatever destination you want. Cost is not much more than a shared cab and so worth the $'s. I can't think of a better way for them to be welcomed.

I'll also second the recommendation for Beach Bar lunch in Cruz Bay. For something a bit more upscale Waterfront Bistro (also in Wharfside Village) has been good for us in the past.
Chip