Problems copying DVD-RW in VR mode & problems making compilations

Please help!!
I’m a 58 year old noobie that needs a bit of expert help.
I have been transferring my large and interesting VHS collection (over 1000)onto disk using the excellent SONY RDR-GX7 and have been creating disks that may have up to 4 or more separate programs on the disk with similiar topics, (e.g. actor’s biographies,music performers in similiar genres, film history, etc). I archive using good quality media (SONY,TDK,MAXELL DVD-Rs),but also have done a lot using DVD-RWs formatted in the VR mode for the ease of editing and setting my own chapter marks. I also record new shows from TLC, History, PBS onto DVD-RWs in VR mode and edit them, take commercials out etc. again all on the RDR-GX7. To back these disks up or make copies for a friend, I have a HP Pavilion a330n which only burns plus media, so a couple of months ago I purchased the SONY external DRX-710UL which can handle ALL formats, comes with Nero software. Also got DVDWizardPro and find it very easy to use with DVDencrypter. Here are my two questions:1.When I try to backup or copy any of the DVD-RWs in VR mode using either DVDencrypter or NERO 6 or Xpress, it goes through the process fine, but right at the end I get a “failure” notice and I want to know how I can backup my -RWs in VR. Can it be done, or am I missing some important point? Help!!
Question #2:I need a simple explanation as to how,(or if) I can assemble a disk compiled of selected programs taken from several disks. Should I stop putting more than a single program on a disk or what?

As you can see, I’m not interested in copying protected movies as many are,
I am also not interested in editing on my computer, as I do all editing I need to do on the RDR-GX7.

Any suggestions,directions or help would be REALLY appreciated. Sorry to be so long-winded, but this “newbie” feels like a “boobie”!!! LOL