What's The Difference?
Theater Rooms are dedicated rooms in which there is full control over lighting conditions and are used primarily for but not limited to movies and shows. Equipment is typically housed in a central rack, seating usually consists comfy recliners, and the room is generally isolated from other distractions. It is as the name applies a movie theater at home.
Media rooms are multi-purpose rooms which are typically used for watching movies and shows, playing games, and entertaining. Equipment may be hidden away inside of a console, seating may consist of a couch instead of movie recliners, and the room in general is more connected with the rest of the household. Lastly, lighting in this room is flexible not needing to be pitch black.