Hi, I am married with no children and the first place that comes to mind is Atlantis in Nassau, Bahamas. I am going there 10/16-10/23. I own a timeshare in Atlantis, I love it there. Everyone is calm and relaxed, you really get the royal treatment. And specific to your request it is an all inclusive type of resort.
my husband is in antigua for work now. he says its real nice. weather is in the 80s. I spoke to him today he says they have a sandals trhere that is supposed to be undeatible for couples.
From my experience if you want to party hard, mexico cancun, many good all incclusives there.relaxing turks caicos nice all inclusives, st.martin very interesting no good all inclusives. if i think of more i will let you know