Well assuming everything was done correctly, it will look fine since people have been making DVDs for 2 decades now 🙂
So it’s either theres something in your workflow that is off or you’re expecting too much…..it’s impossible to know from here. :).
As an editor, You need to know the complete workflow…..how was it shot? How was it captured? What format are you exporting, ect FCP is very helpful in determining where there’s a short in the process.