I've seen CD writers that are also DVD readers but not writers, one of them in a dell recently. check the logos on the front of the drive. If it says DVD-ROM or just DVD, it's probably just a reader, it you see things like DVD+R or DVD-R, then it's a recorder, and I would suggest trying different burning software and upgrading the drive's firmware (check manufacturer's site).
dylanscomputers.com, January 2010