I've been to CBR twice. I've visited POR but haven't stayed there. Although you'll have fun at any one of them, here sre some tips that I think will help you enjoy more your vacation in CBR:
1-The resort is divided in 2-story building clusters named after Caribbean Islands: Jamaica, Aruba, Barbados, Martinique, Trinidad North and Trinindad South.
2-Request a room in Martinique, Trinidad North or Jamaica
(Warning: Many rooms in Trinindad North are Smoking Rooms).
These are the buildings closest (in that order) to Old Port Royale (Food Court/Main Pool). If you stay in Jamaica, you'll have to cross a footbridge, but it's not that far.
3-Trinidad South and Barbados are the buildings farthest from Old Port Royale. Unless you REALLY like to walk or jog, avoid.
4-Each 'island' has a bus stop. The first bus stop is Jamaica.
5-Each island has a quiet pool and a beach with hammocks (no swimming in the lake, though).
6-CBR has a huge lake where you can rent boats to cruise arouns. It's very nice.
7-The Front Desk and Guest Services are in a separate building near the entrance called the Custom House. This could be a long walk if you like to check your charges periodically throughout your stay, or if you plan to use Guest Services frquently.
8-The island buildings have no elevators. Keep this in mind if someone in your group has a wheelchair, or has trouble going up stairs (mention this when making your reservation, so that they try to accomodate you on a first-floor room). This is also something to consider if you'll be carrying tired/sleeping kids when returning to your room. That being said, second-floor rooms that aren't close to the stairs tend to be quieter, with less foot traffic.
Hope this helps. I'm sure you'll have a great time!