GIGABYTE GA-MA785GM-US2H audio setup

[Guest]

On GIGABYTE GA-MA785GM-US2H motherboard; I need some guidance in setting up my audio.
Looks like I will be using S/PDIF Out Audio port to send Audio to YAMAHA 5.1 A/V Receiver RX-V365. Receiver doesn't have through HDMI functionality. I am also using onboard graphics card for video on my 1080p TV

I have few questions:
1. Is this correct setting.
2. How can I disable HDMI audio in this case, and also other 8port output analog port.
3. I also have LG blueray player, do I have change my Windows7 system audio setting so that I can get excellent music to my AV Receiver. AV Receiver has Dolby Digital DTS Digital and Dolby Pro Logic II Decoder.

Thanks for your help and time.

 

[r_manic]

2. If both ports are integrated into your motherboard, you can disable them in the BIOS.

3. go to control panel and access the audio settings to set a default audio device for your computer.