According to the fair use law of copyrighted material one may only distribute copyrighted material (edited or not) for
none of those uses are...criticism, comment, news reporting, teaching (including multiple copies for classroom use), scholarship, or research...
None of those qualifications are met for AMV's. Therefore, the transmission of any AMV is in violation of copyright laws. One can not "sell" a DVD of AMV's at all, if they don't want to break the law....an infringement of copyright.

Ethically: Internet distribution and non-profit distribution via DVD's is considered to be "OK" (or at least that seems to be the consensus)