Yes the passport book (not just the card) is required.
Yes, according the area’s travel website Negril is safe, however, you should not venture away from the resorts at night.
Yes, absolutely! Airfare, food, lodging, beverages, and entertainment are all included within the cost the will be provided to you. The cost is relative on how many people and exact accommodations.
English is the official language.
According to online there are several recommended vaccines for Jamaica. Some of these include; Hep A, Hep B, Typhoid, measles, etc. Make sure you take your bug spray!
The official currency is the Jamaican Dollar, however, you can use US dollars at the resort.
During the day the standard dress code is casual. At night, however, most restaurants and clubs will require a nice dress, dress shorts or jeans and collared shirt.