could you be more specific with the movies? like the audio format of the file? & the player you are using?
Firstly, you need to make sure the video file supports the 5.1 encoding (DTS/DD), if you have done that make sure that your AVR is on the 'auto' mode and not selected to 2.1, if most your existing files are 2.1 encoding as would most likely be the case, just enjoy as is, or max you can do is output sound out of the 5 satellite speakers.
For movies I can have proper check only when I am back there and have a careful look. But what about game ? As mentioned earlier, I tried CoD:MW2 with audio settings set to 5.1.
Also I hope it is a PC to AVR to TV connection via HDMI.
Although it cant decode HD-audio, it can accept LPCM decoded by BDp, so can enjoy HD-audio too.
Nope. I am yet to buy TV - probably have to wait 3 more months. Currently display is on Dell ST2220L via DVI and audio routed via HDMI to AVR, both from my graphic card - HD6950.