What i'm saying is get a blu ray player or DVD player that has the 5.1 or 7.1 analogue outputs
These types of players will automatically decode whatever digital audio is being used on the disc & output it to the analogue outputs. Ok, so you'll need a few more wires than a single HDMI cable, but there are no compatability issues
So yes, use the RCA connectors & run analogue.
If & when the bright sparks come up with something even newer you'll only need to replace the player with the new kit & as long as it has the analogue outputs you are laughing.
Joe Bloggs who has his amp/receiver doing the decode needs to replace both his player & the amp/receiver
Well that is unless he switches over to the analogue inputs on his amp/receiver (if it has any).
Hope that helps & yes, you did get a real bargain!