I am having the exact same problem, after three years I never even tried burning to a Sony DVD-R disc. CD-R disc present no problems. The Sony disc shows 0 capacity on any type of DVD-R and DVD-RW, firmware update fix nothing! Looking for a DVD-R drive that can write at full speed with no problems later when trying to retreive the data, recommendations? I have tried multiple discs to ensure that it isn't the discs.
Try that disc to another pc, if it works then it's not the disc, try that DVD drive to another computer if it work then it's your unit. Use the IDE or SATA cable that worked with the other pc or the power cable that work. If that won't work then it is a driver problem - you can check microsoft for this or third party tools for driver. Rarely if your OS is updated you won't have this problems.