Guinness Mann wrote:
unitron wrote:
If it's digital, why would there be *any* difference in either the
sound or the picture between the original and the copy?

Because most DVDs won't fit on DVD+/-R media.

That applies only to DVD's that have more than one layer.

All of the DVD copy
programs I know about either leave some things off the copy (typically
at least some of the audio info) or add compression.

No, they just copy the data to more than one piece of DVD-R media,