You will have many more AI choices in Punta Cana. Also, depending on where in Belize you go, options for beaching are not great. Ambergris Caye and Caye Calker are mostly for boat rides to the reef; the sand is hardpack and there's lots of beach grass. If you go elsewhere in Belize, you might have walk-in snorkeling, but the lodging options are not what you seem to want.
(Belize really seems more for adventure/Mayan ruins/river and cave rafting, exploration and diving, vs. all inclusives, whereas Punta Cana has dozens of choices and lovely beaches.)

There are only a couple of true all inclusive properties in Belize, Even then, they probably aren't what you're thinking of. They're small properties, probably less than 50 rooms.

Kanantik is one, I've never been, it looks lovely.

Belize is a small country, easy to get around. Many people who come split their trip between the inland area where the Mayan sites, caves and rivers with waterfalls and such are, then head to one of the beach destinations.

We're seniors as well, love Belize, heading their in a few weeks.

Thanks soooo much for your help! In Punta Cana, I am looking at Paradisus Punta Cana or Paradisus Palmas Real. Has anyone been to either....and if so, how did you like the resort? Also, how is the food in Punta Cana? AND,.....do they speak English?

JeanH....When you go to Belize, is it more for the adventure as opposed to the beach?

Thanks again for all your help!
Beachbum022

When we first started going to Belize, it was mainly for the beach, along with snorkeling and diving. For all of our trips, we really haven't spent much time on the mainland. Now, we go mainly to see our friends and just relax.

We never have spent much time just lounging on the beach, we spend lots of time wandering the beach.

The restaurants on Ambergris are varied and good, lots of beach bars. I've never stayed at an all inclusive resort, I like trying new restaurants.

Victoria House on Ambergris, Belize is amazing - beautiful white sand beach, pretty water, good food, and great snorkeling if you take a boat ride out to Hol Chan. The sand is soft and pretty. There is sea grass in the water close to shore. It's not an all inclusive spot. Not sure if that's a deal breaker for you. It's easy to go into town for good restaurants, and there's also a bar and nice restaurant where you can eat. It's a little pricey though. We like Belize for the adventure activities, ruins, and snorkeling.

Those boat rides every day to snorkel get pricey; and, if you walk along the beach anywhere else but Victoria House (done the stroll many times), the sand is not soft and pretty, and the beach can be quite narrow (it's also a major pedestrian throughfare for workers and students, depending on the time of day). Plus, you have to fly/ferry there.
I love Belize, but given your description of what you want, Punta Cana sounds like the ticket.

wow, I thought this was a different but similar thread; looks like I butt in with my 2 cents twice! sorry about that.

Have you looked into Tranquility Bay on north Ambergris Caye, Belize?
http://www.tranquilitybayresort.com/

You can check out the blog post from our August visit here:
http://hopefulistinlatinamerica.blogspot.com/

Have a great trip, whatever you decide!