Nearly all mainstream films and a growing number of adult films are CSS copy protected. There are other copy protections out there but CSS is the most often used.
I don't know about the USA. But in Germany its totally illegal even for home use.
The usual software like Nero or CloneDVD doesn't copy protected discs. And software to crack CSS is illegal.
In the United States, making a backup copy of copyrighted material that you own for your own personal use is legal and considered "fair use" (provided you retain rightful ownership of the original item).
Last year the copyright laws were changed due to massive pressure by the film and music industry. Now in Germany you are only allowed to back up your own DVDs if you don't have to crack a copy protection to make a back up.
Yes and no. Copyright wise, no problem. BUT, the Digital Millennium Copyright Act makes it a crime "to circumvent anti-piracy measures built into most commercial software." Digital Millennium Copyright Act highlights
So, while the concept of "fair use" is long established, nothing says the copyright owner(s) need to make it easy to do. Making a "fair use" copy is legal... but defeating the copyright protection measures to do so is now a crime.
Interestingly enough, this is the polar opposite thinking when compared to "head shops" and drugs. Selling bongs and roach clips was legal, yet their intended use (i.e. taking drugs) was against the law.
Once again, discussion of copying DVD's is not permitted at ADT. If you want to find information on this topic, I suggest searching the rest of the Internet for anwswers because they won't be found here.