Hi Mark.
No experience with that motherboard.
I think the 8500 video card may be "too new" -- You'd be better off with an nVidia 6200 or 7300.
Audio not sure, I would guess OK.
There are only two entries for AverMedia in the wiki, neither one more than a few lines. The tuner card you need depends on if you want SD or HD. There is plenty of discussion about tuner cards in the Wiki and Forums.
I think it's hard for anyone to say for certain if your collection of goods will work. The bad side of things is LMCE can be very picky and not all of us have the luxury of "trying" one system, and then another, and then another until it works ;-)
Give it a whirl and if it works, add the details to the wiki for others.