St. Barth's has everything you are seeking - fine beaches, great restaurants (some of the best in the Caribbean), shopping and sophistication. It's very French and tres chic. Look into staying at Le Toiney or the Eden Rock. Use the search feature above to find recent threads on St. Barth's (you'll sometimes see it written as St. Bart's). Also go to www.sbhonline.com for a very active forum on St. Barth's.

St. Martin is much more commercialized and and very crowded. La Samana is the most upscale resort on that island but it get's very mixed reviews. If St. Martin is like going to France, St. Barth's is like being in Paris. Martinique and Guadalupe are "off the beaten path as far as tourism is concerned and will not have the upscale resorts, selection of restaurants or fine beaches you are looking for.

St.Barth's/ rent a villa there through Wimco (West Indies management company) with cook/housekeeper and childcare services for more flexibility and privacy than a resort. If you want resort, check the smaller boutique Le Banane or the more formal Guanahani, Eden Rock or Francois Plantation. Bring money.

When you say "off the beaten path" would you mean more that it is somewhat secluded and private, or that the service wouldn't be up to our expectations?

When I say "off the beaten path" I meant that services on Guadalupe and Martinique might not be up to your standards, i.e. you won't find exceptional accomodations or the great restaurants that you are seeking. There's nothing on either island that comes close to what you'd find on islands like St. Barth's or, to a lesser extent on St. Martin . Guadalupe and Martinique are not very tourist oriented so they don't get anywhere near the number of visitors to those islands vs. visitors to St. Barth's or St. Martin. Less visitors translates into less amenities - it's as simple as that. Beaches on those islands are generally small with darker sand. The islands are not "lively" and you won't find great spas.

There was a recent thread discussing Guadalupe about two weeks ago which gives a good explanation of the island. Use the search feature to find it.

Given your perameters, St. Barth's, if you can afford the price tag, is where you should look first. I also agree with tivertonhouse that Guanahani and Francois Plantation are worth looking at.

The level of accomodation in Guadeloupe and Martinique is mostly in the 2/3 star range, apart from a couple of exceptions.

I'm sorry to bring contradiction to Sunnyboy but most beaches on both islands have clear sand.

Regarding spas, there are not that many I'm afraid.

One point is that you will have to struggle in French most of the time. English is spoken sometimes but not on a current basis, since most visitors originate from France.

However many Europeans and more Americans are now visiting these islands, so the situation re/English is slowly improving.

Thank you so much for your much needed insight. Just wondering, when you say English is not spoken much on these islands, are you also speaking of St. Barths? I can speak conversation French, would we be OK with English as well though on St. Barths?

Other than Merci, Tres Bien and Bonjour I don't speak a word of French and have never had a problem communicating with anyone on St. Barth's.

Yes, English will be no problem in St Barth. Enjoy your trip !

Based on your description, Saint-Barth probably fits your needs best. It's a wonderful place but be prepared to pay. If you don't mind outrageous hotel bills, places like Le Toiny or Isel de France are hard to beat.
Of the FWI, St. Martin is the most tourist-oriented and popular with Americans, and the one where English is almost univarsally spoken. Saint-Barth is much more French, but is sort of bilingual the way Montreal and Quebec are. Either language works fine. Guadeloupe and Martinique are both beautiful but make basically zero effort to cater to American tourists. There is far less English spoken on these two islands, and your visit there is a different (and better) experience if you can speak French.