Rooms are available about 1:30 to drop your carry ons. Checked luggage can arrive any time, but we usually have it before 3. We usually arrive at the port about 11. They start delivering luggage essentially right away, and really try to have it all delivered to your cabin before the safety drill. However, the official line is that it will be delivered by 7 (or something like that). We've always (10 Magic cruises) had it before 5, no matter what time we got to the port.
You can have 2 checked pieces of luggage per person. Your husband's medical equipment will not count as a piece, whether you check it or carry it on. You can carry on as many pieces as you like, but remember that you will have to drag them around till the cabins are available--thus, it is smart to pack only what you really want/need in the carry ons. Then add swim suits. One of the best times to swim is between boarding and the safety drill--the pools are empty.
Label your carry ons with your name on some sort of luggage tag--just for safety in case you leave it somewhere. Put the cruise tags on the checked pieces.
So...you can have 6 checked pieces for a family of 3, PLUS your carry ons.
To answer another question--you put your cruise tags on when you are leaving WDW for the cruise (since none of us are on the land/sea). DO NOT put them on when you leave home if you are going to WDW first. You will need to claim them at baggage claim, take them to your transportation to WDW....and then put the cruise tags on when you leave WDW.
We have been able to put them outside our room at the resort and call the bellman, then not see them till we were on the cruise. Of course, that only works if you are taking the WDW bus to the port. However, again since we are not on a land/sea combo, DO check with the bellman at your resort. Simply ask the bell captain whether your bags will be held at the bell station for you to give to the
DCL transportation people or whether they will get them to the bus for you. You want to be clear on this point as you don't want to get to the port and find that your bags are in the luggage storage area at the resort!