[upwardr]

I've been to Cuba about 15 times and have had stomach issues one time. Varadero is a good place to start. Don't rent a car take a cab or bus charters. They are inexpensive and cabs will wait for you for return to hotel. You can travel in old 57 Chevys and fords.
We went to a baseball game in Havana and spent the day there it was a good experience. Rules for the population have relaxed and they are allowed more private businesses.
The beaches are simply amazing, Varadero has miles of clean white sand turquoise water. Not to be missed. We took a day snorkelling on a bus tour to the Bay of pigs on the south shore, think it was like 30 bucks ea for the day.
Holquin is also nice, clean beaches but less for the kids to do.