If you have the SPDIF Out box checked, then you will get no sound at all. Your selections should be:
Audio Channel: 6 channels
Sample rate: doesn't matter
Analog out: 5.1 speakers
SPDIF Out: NOT checked
Virtual speaker and Pro Logic IIx are a preference thing, and you will just have to play with those to see if they suit your tastes.
Also make sure Hi-Fi mode is not on... it may force stereo. I don't remember, because I'm using the standard C-Media interface instead of ASUS' proprietary stuff. So, I don't have Hi-Fi mode or SVN.
Putting the card in 4, 5.1, 7.1, etc, will send music to all the speakers. I'm listening to it that way now. You may prefer 2- or 4- channel sound for music though. It depends on the quality of your center, spacing of the speakers, etc. Try different modes and decide what suits you best. I find 4-channel mode best for my music needs.
It's hilarious that the same people who laud the "benefits" of 16x9 aspect ratios also praise Chrome for "freeing up screen space."
Windows XP will never die!