Saturn,

For non-24/96 content, the decision to use the analog outputs boils down to wether the DVD player has the better DAC or the receiver/pre-amp. Whichever has the better DAC will do the best job of converting that bitstream into an analog signal for amplification. For 24/96 content, you'll have to either use the analog cables or you'll need a receiver/DVD-A combo with Firewire (there are also a few cases where individual companies produced high bandwidth, proprietary digital connections such as the Denon AVR-5803 and DVD-9000).