My "D" drive reads discs, plays CDs .etc., but won't read the DVD-RW disc when I try to burn a slideshow movie from my hard drive. I"ve tried searching help, etc. and it appears that I need to "format" the disc before I burn files off the hard drive onto the DVD-RW disc. When prompted, the temporary files are ready to copy and when I insert the disc to copy the files, the computer doesn't see it, so I'm dead in my tracks.