You do have 3 ways to connect your DVD to your Home-Theater system. It depends on the features of your DVD and you Receiver or Surround Processor

Figure 1: It is for the old system that your receiver has 5.1 channel input. So you have to add a DVD player with AC-3 Digital output and a stand-alone Digital Surround Processor Decoder. So, you use a digital interconnect to connect your DVD digital output to the digital input on you DSP Decoder; then, use 6 analog interconnects to connect 6 analog outputs on your DSP to 5.1 inputs on your receiver.

Figure 2 : It's the same as the figure 1, but you have a DVD player that has a built-in AC-3 decoder inside. So, you just use 6 analog interconnects ( Front Left, Front Right, Center, Rear Left, Rear Right, and Subwoofer ) to connect from you DVD to you Dolby Digital Ready Receiver.

Figure 3 : The best way and best sound to connect the system. You will use a digital interconnect to connect from your DVD AC-3 digital output to your Dolby Digital (AC-3) Receiver / Surround processor. To connect this way, you will save a lot of money to buy 3 pairs of analog interconnects. A good one will cost you more that a $1,000. This figure is great for your separated components. I also use this figure in my Home-Theater system.