Looking at your picture I would expect that to be two groups, one for the wall, and one for the door, including the handle. The door would be made a child of the wall, and the rotation point of the door would be moved to inline where the hinges would be.

As an experiment it might be worth importing the wall and importing the door as a seperate object and then using the joint editor to move the rotation point of the door over to where the hinges would be. Then when you rotate the door on its Y axis it will open just like it was a figure. This will give you good practice on using the joint editor, which takes a bit of practice. You will need to be familiar with the joint editor if you are going to rig figures ;-)

Going further, if you wanted to have the doorhandle turn, then you would have three groups:- the wall, the door, and the handle The handle as a child of the door, and the door as a child of the wall.

As you say it is a bit OT for the thread, and there are some great tutorials which explain rigging much more clearly than I could.

 

Hope that helps ;-)

Oh you worked it out while I was afk. Thats great ;-)