Preferred v standard room types?

Thanks to everyone for the help so far :)

Can someone help me work out if its worth paying more for a preferred room or building? what does it actually mean?? the disney phoneline said it was just closer to the main building, is that all or will the room be bigger and better?

They are closer to the main building and I believe some have bathrooms set up for wheelchairs. Other than that they are the same size as the other rooms.

Is a preferred room the same as a concierge or are they both different?

No, concierge is different and usually much more expensive. Where are you staying?