Here you can see a "non" working home theater system with projector and screen that can be used to decorate a living room in Minecraft.

Instructions:

The projector should hang down from the ceiling with a cobblestone wall (or wooden fence depending).
As a lamp, a fakel is used (put on the block in front), then place a frame and in the frame put a black wool block. On both sides put a stone or wooden knob and then the frame.


The canvas should also hang down from the top with a cobblestone wall, as canvas you should mainly use only white wool blocks or another white block.


You can still add bench seating or a couch.


Best is to use black glass as blackout. Or no windows at all, just lights that can be controlled with redstone and a hoist.

Feedback in the comments please :).