On the Radiance we took a brige tour, but that was the first time they have opened the bridge in a long time. It is left up to the Captain as to whether or not he will open up his bridge to tours. I have taken Galley tours on several ships. As far as crew areas or any "below deck areas" they are off limits for a number of reasons -- mainly insurance and safety reasons.
As I posted on another board, it used to be fairly ewasy to do and some areas had regular tours. With the new security crackdown unless you happen to be a longtime personal friend of the Captain then your chances are nil of accessing these restricted areas. I would also be careful about 'accidently' wandering into these areas for anyone that thinks of trying that as it may well now involve not only your being stopped, but thoroughly questioned and possible reported to the FBI with more questions to answer upon arrival in your homeport. Safety is a huge concern right now and they aren't playing.
My son works on a cruise ship so I was able to see both the bridge and the crew quarters. The bridge was very interestng and the crew quarters were depressing. He's an officer so I can only imagine what the crew sleeping quarters are like-four to a room and bath down the hall.
You stated it correctly everthing is off limits right now.For security reason's but you can alway's see the area off limits on the T.V. If you do happen to wonder off the limit's you are stopped and held until they check everything out on video of where you have been and what you were up to.