NEC ND-3520A not completing burn

I am very new to DVD burners and just received the 3520A a couple of days ago. I am using X-copy platinum to back up movies. I haven’t had it finish a burn yet. I have made 6 very nice coasters so far. My system is a HP Vectra Pentium celeron 850 MHz with 128 megs of ram and a little over 10 gigs of hard disk space remaining. The DVD writer is set up as the secondary Master and a DVD-ROM is set up as the secondary slave. I am running Windows XP Pro with SP2. The movie I am trying to back up has been backed up before by a friend of mine using X-copy Platinum. I don’t know anything else about his system. Would anyone know what the problem might be? I would really appreciate any help. I haven’t received any error messages just told the burn stopped and to look at the log file. When I do it basically tells me the burn completed or stopped. Not much help there.