This is a really basic design: R2D2’s body is essentially a canister of Blu-Ray discs (approximately a dozen discs). Each disc is accessible via an extending drawer:
Each drawer is manually opened. To ensure the disc is fully clear of R2’s body the drawers would telescope (almost like extending the dinner table to add a center cross piece).
This case would be on the bigger side: about 7″ wide and 9 - 10″ tall. Given its size I feel it has room for lights and sounds, which I’m sure most fans would love.