Hello noobie_uds and welcome to the forum.
First, use some other kind of discs and try a burn. It is possible that the batch of discs you have is just bad, or the discs don't agree with your writer. See if you can just buy a single disc in a jewel case. That way, if it isn't the discs at fault, you won't be stuck with 24 or 49 other discs.
Next, change the IDE cable connected to the DVD writer with a new one. The cable could have gone bad. Cables are remarkably cheap things, and the less expensive something is, the less quality control measures can be afforded as production costs on the items.
If this still doesn't work, then the only thing left to do is to try the drive on another computer. If it works there, then it may be something to do with your computer (probably something with windows). If it doesn't work there, then the drive is probably faulty.