zach said:that's his point, i think. he takes it out from the library and simply has it pre-ripped onto his harddrive so he doesn't have to even put it in when he has it out.
even if it's not out of the library, it's a freely available public resource, as it's at the library, and as long as he's not burning and distributing copies, you can make a very strong case that using/ripping a DVD like that is totally legal under fair use.
it may not be in the spirit of the law, but it would be pretty hard for anyone to actually win a court case against you for that kind of usage.
That's assuming he only uses it like he would with the library copy: to watch it for a brief time and not keep it indefinitely.