i made a copy of one of the DVDs i own. when it was done, it gave me some error message about bad sectors or something. but when i tried playing the DVD in my player, it seemed to be working fine. had all the extras, features, etc. for the first 15 minutes or so, everything was perfect. however, after a certain point, it began skipping, then eventually freezing. i FF'd through some chapters, and still the same. just kept skipping. i use Verbatim DVD-R dvd's. used MTR to rip. DTOX to compress. and Toast to burn. any help, advice?