Trouble editing NTSC dvd

Does anyone have any suggestions for editing a noncommercial finalized -r NTSC DVD, recorded on a DVD recorder? The DVD has one title (with possibly an empty title after that). I am fine with retaining the original menu structure (or not): all I want to do is remove the first nine seconds or so from the beginning of the DVD and write out the result to a new DVD that will play on a DVD player. I've tried various packages with no success. Is the combination of -r and video recorder uneditable?

Thanks for your help.