PC Sound Card Connection to Denon AVR-2805 or Samsung 40B610

I have the following equipment and would like to know what is the best, easiest and least expensive way to connect them together to get the best sound output. I have an Auzentech HDA X-Plosion 7.1 DTS Connect Sound Card on my PC that has both a coaxial and toslink connection (supplied toslink cable). I have a Denon AVR-2805 Home Theatre Receiver. I have a Samsung LN40B610 LCD-TV with coaxial input and toslink output as well as regular RCA audio output (which I am presently using to connect to the AVR-2805). At present I don't have a HD - Digital Tuner but will in the near future. I am not sure if the HD Tuner makes any difference in the connection for pc sound or not. Video is not an issue but sound is from my pc to anything. I also have another spare toslink cable. Should I be connecting my pc sound card directly to the receiver or to the tv then to my receiver to get the best sound output? When I get the HD Digital Tuner, does that make any difference for the pc connection? I do know there will be a HDMI connection from the tuner to the LCD tv. Please HELP!!! Thanking you in advance.