OK , time for a reality check! The "wish list" in your post you listed in your post is much to general. You can find beaches to relax on, places to shop, good food and some nightlife on just about every Caribbean island (I know of only a few that don't have beaches, per se).

Here are some hints to help you:

1) It's always best to give us an idea of your budget for accommodations, food and airfare - terms like "budget is flexible" don't help much since we don't know what 'flexible" means to you. Are you flexible enough to willing to spend $3,000, $5,000 or maybe $20,000??? How much you are willing to spend can make a big difference in recommendations you receive.

2) All Inclusives - destinations that are known for All Inclusives include the Dominican Republic, Jamaica, Cancun, Cozemel, Playa del Carmen and to a lesser extent Antigua. Some resorts throughout the Caribbean do offer "meal Plans" but are not really All Inclusive.

3-A) Good food/restaurants - by an large most All Inclusives have mediocre to average food unless you are staying at a very high end AI Resort. If good food is a priority forget All Inclusives.

3-B) Islands know for having exceptional restaurants include Anguilla, St. Barth's, St. Martin, however, you can usually find some excellent restaurants on every island.

4) Night life - generally speaking the "major" islands will have active night life while the smaller less populated islands will be much quitter. However, no matter where you go you'll always be able to find some place that has some form of entertainment at night but the more popular islands will have more of it. Think about it, the more people there are on a given island the more amenities it will have - no one invests money in a business if there's nobody around to "purchase" what is being sold.

5) October is smack dab in the middle of LOW SEASON and HURRICANE SEASON in the Caribbean. While room rates are at their lowest of the year many resorts are closed as are many restaurants and tourist oriented businesses so that could limit your options. On the plus side, there are few crowds. While it's impossible to predict the weather this far in advance there is always a possibility a major tropical storm or hurricane could be brewing nearby the island you are planning to visit. If that happens there could be several days of very unsettled weather. Consider purchasing Trip Interruption Insurance if you have to lay out a lot of non-refundable deposits. The further south you go the better the odds will be you won't encounter a major storm - but there are no guarantees.

So, I suggest you first do basic research. Use the "Destinations" link at the top of this page, click through to the Caribbean. Read the general descriptions of each island listed - you'll find they are all different. Pick one or two that most interest you and then use the search feature to bring up recent posts about those islands. After reading some of the threads you'll have a better feel for each of those islands. You can then start researching resorts on those islands. Try not to get caught up in "is the beach better" on the other island syndrome. Since this is going to be your first trip to the area there's no one island that's better than the other, they are just different. That's what makes the Caribbean so interesting. You can visit a different island every trip and not see it all. For example, I've visited some 35+ different island in the last 20 years , have a home on one of them and every year I still visit others.

www.weather2travel.com/climate-guides/aruba/oranjestad.php
Someplace low rain out of the storm belt best in Oct.
Not the best time to go due to storm risk.
Like Hyatt Palm Eagle Beach Aruba
Might also consider Cabo Capella Pedregal
low rain private plunge pools or
princeresortshawaii.com Mauna Kea or Hapuna Prince
konaweb.com where I go for less rain in fall.

Congrats!

Pool & Private Plunge Pools. ... Each of our bedrooms and suites at Capella Pedregal offers a private terrace featuring a plunge pool with spectacular views of the ...

www.capellahotels.com/cabosanlucas/facilities-en.html

If budget is not a big problem, checkout Boaose resort in Curacao. Awesome hotel on an awesome island.

Given that you chose October, I would go with Aruba, Curacao, or Barbados. However, Aruba has had it's share of tropical storms the past couple of years in an October. I didn't find much nightlife in Curacao.

If there is any way you could postpone to the first two weeks of November, you will have a greater chance of seeing better weather.

Thanks everyone! Comments and suggestions have been helpful.
To provide more info in response to the first poster, we don't really have a budget. We are doing this instead of a big wedding.
The more we've looked into it, we've decided postpone it until end of November to avoid the potential hurricane.

First of all...Congratulations!! When is the wedding?

My first response was Aruba. Now that you have chnaged it to end of Nov my response is still Aruba!

We love Aruba! We take Air Canada's direct/non-stop from Toronto to Aruba. About 5 hours.

First time we went to Aruba (11 years ago)we stayed at The Marriott Hotel on Palm Beach. Since then we have been staying at the Marriott timeshare property to the south of the hotel: Marriott Ocean Club. Go to www.redweek.com to find rentals. Or www.tug2.net
Redweek is usually better.

Or, consider Radisson south of the Marriott properties. You can do this thorugh www.aircanadavacations.com or on your own: Book your flight through www.aircanada.com Then your hotel through Radisson.

Aruba has lots of great restaurants so I wld not recommend AI for Aruba.

Hope this helps.

Ocean