There are always multiple Cirque du Soleil productions going on in Las Vegas, but "O" is unique because it is the only one where much of the activity takes place under water. "O" has been running at the Bellagio seemingly forever (this reviewer saw it more than a decade ago), yet it continues to be performed twice nightly every night but Monday and Tuesday before capacity crowds. This may be one show that will never close.
The international cast consists of world-class acrobats, synchronized swimmers, and divers. Ticket prices are a steep, but worth every penny, $155, $130, or $109. The hotel concierge can make the arrangements for your family which, if you wish, can also include dinner. However, the dinner-show packages limit you to a few specific choices only at one of the hotel's more expensive restaurants. If you have young kids, you might be better off choosing another restaurant at the hotel that is not quite as expensive and where the food is more child-friendly.