Though your link does not work, the PC/DVI 3.5mm connector is probably an audio input (and not an output), in case you're using a connection that does not pass audio (DVI or VGA).
Your TV could probably handle 2 channel dolby digital via HDMI. Most HDTVs could handle Dolby Digital because it's used extensively in digital satellite, digital cable, and terrestrial high-definition feeds. The digital out may also be able to bitstream the unaltered audio feed to an external device.