If your receiver has an audio "Input" that is "digital" or "optical" cable (fiber optic), that's all you need. The DVD player will spit out whatever audio the DVD is capable of, and the reciever will do the rest. One of the better reviewed DVD players is the OPPO Digital unit ($149 to $199), but they are not full HD players. They upres to either 1080i or 1080p. The OPPO players do everything that you could ever want, including playing Dvix discs, DVD audio, MPEG images, etc.
We have an Onkyo 7 channel surround system. We would like to purchase a DVD player to take advantage of this system. Due to cost, i do not think we can go to full 7 channel yet but probably could go with 5 channel. On the "specification" tabs, what type of terminology do I look for to tell if a player has 5 audio outputs? Are they any you highly recommend as good mid range price players?