It's interesting to note that the word "pirate" has changed definiton slightly over the years. It used to mean those who had businesses selling lots of copied films. Now it tends to be the term for anyone that copies a film.
spaced: I would urge you to follow what you believe to be morally right, and ignore any laws. If you have bought a DVD, then you should be able to do what you want with it, i.e. share it with your friends, make some copies of it, etc. I'm sure the actors in the film would like to get their name and talent recognised, and it's only the greedy executives of the film companies that want to stop you sharing the film, to make as much money as possible.
However, I'd argue that copying a disc from a rental company isn't very moral, as the people working hard to make the film in the first place won't really be benefiting all that much.
Some may argue that ignoring the current laws is wrong in some way (apart perhaps from the obvious, that it could land you in jail); slavery was once perfectly legal here, but I certainly would never have called it moral, regardless of the law. Laws don't mean much, and many of the ones we currently have are a waste of time anyway.