Hello

I would like to know how to edit a disc I copied from an original disc. I have a Sonic Digital Media 7 and a MYDVD pops up when I click edit disc, on the MyDVD a browse folder pops up and when I click something I keep getting a please select your dvd root folder. I don't know what that is or what it means. I can't get past that screen. I want to edit a DVD-R, actually trim some of the beginning and end. I would appreciate any help. Thank you