If you are asking us for recommendations as to which cruise line or indeed which ship would best suit your needs then you might get a good response but if you are asking for specific deals then it is better to go to the "horse's mouth" i.e. a cruise agent as above. If it is the former then can I suggest that you be more specific with your definition of "all inclusive". If you mean free food and entertainment then all ships except Easy-cruise give that but if you mean free drinks then there are usually only the lower star and the highest star cruise lines offering this and often to equate "relaxing" with some of these lines would be more difficult. So.... give us more information and we will reciprocate... Neil.
The Arcadia is one of the ships, adults only. Call 0800 091 1629 and enquire further from the cruise desk.
Cruise.co.uk is promoting an exellent handbook on cruises. I recommend that you get hold of it it covers everything, is neutral and will help you come up with a shortlist. Worth looking at the Cruise line reviews on this website and Cruise critic.