Answer:
Firstly, 'copyright' is the ownership of intellectual property. It has nothing to do with physical copy protection. Your DVDs or CDs are copyrighted to you inherently, the moment you create them, and when you created the content too. No software is needed to copyright anything.
Secondly, there is indeed software that can burn DVDs or CDs in such a way that creating an unauthorised copy will be more difficult - typically, they don't 'prevent' a copy being made, they just use certain tricks to make sure that the copy is unusable. But to be honest, it's only really making it difficult for yourself.
Is the DVD/CD made to be played in a DVD or CD player? If your version uses specific software tricks, it may actually cause playback problems when played on those devices. Or on the other hand, those tricks mentioned above might stop the copy working on a PC, but less sophisticated devices like a DVD player might play it anyway.
The most secure way is to have the DVD/CD install a rootkit onto the PC, as a form of digital rights management. Sony tried this in 2005, and suffered a lot of negative publicity and legal action because of it. Malware producers were able to distribute malware that used the rootkit's own protection, to protect itself and make it almost impossible to remove. Sony was told by the courts that it did not own the customer's systems and should not have secretly made them vulnerable in that way.
With all that considered, there's also people who no matter what you do, will still find a way around it, and for all those reasons above, it is rare to find CDs or DVDs that have any solid copy protection anymore.