Depends on who you ask. Technically, you have a legal point that stems from the VHS decision, but the **AA folks would probably argue that you are still cirvumventing their digital protection which violates the DMCA. And if whatever program you are using has DeCSS as part of it, they would argue it is illegal since it is a reverse engineer of the DVD decryption algorithms.
If you had the money you could probably fight it out in court for months/years and would win. But otherwise the **AA would win because they have more money and time and lawyers. -- Brian
