I don`t use Roxio, but does it have an `Import` facility on the toolbar?
Usually you would connect either your camera or VCR to a recognised input (capture card) and use the editing software to import it directly. This allows the software to do any conversion it requires.
If you have, somehow, just moved the raw file to your PC you may be able to import it still but may need additional codecs (files that recognise the file extensions above)
If your PC DVD-RW will accept RAM disks you could also import from there into Roxio.