There are a couple of places, that you can go "all inclusive", but why you would is beyond me.
Victoria House is wonderful, beautiful property, and I believe you can get an "all-inclusive" meal package there, but again, in that part of the island, I wouldn't get a meal package, too many other great places to try out. Just take the breakfast part of package, if you want/need that.
Coco Beach pool area, is fantastic!! Had so much fun there, lazing about, going down the slide, etc. But too far from town for my personal tastes, to stay for more than a couple of days of chillaxin'.
All that said, it's personal tastes. If you just want a beautiful place like that to enjoy for the week, either one of those two locations would be pretty hard to beat.