Personally I would have to pit 'Dangerous' against 'Off the Wall'.
Off the Wall, showcased a young yet potential bearing Michael. A very charismatic side of Michael, that you don't exactly hear on the other albums. He was at his most charismatic time, and you could see his evolution from the little kid from that bubblegum pop group to becoming the mature funkmaster.
He was trying to find his style, and you could see how he began to grasp it. His potential was getting to be unlocked and he was in total experimental mode.
Dangerous, is the album that seperates itself from everything. He made a drastic change, and tapped into the New Jack style. The stylistics of his music changed into harder and edgier rhythms. His music in each track told a solid story, or set a major scene. It truly brought Michael into a new stage in his music, and he was at a new era in his life. He was very mature.
Those two albums differ so much. I can't honestly decide......