IANAL, the value of this is what you paid for it and I'm not charging.
When I've looked into this before for the US, it was legal to make an archival backup of media you owned. However, "archival" was a key word - it can't be to transfer it to a more useful medium, just for backup in case your primary copy was damaged or destroyed. Also it was you archiving it - a copy of someone else's version of the same media did not fit the restrictions. So basically, you were allowed to make a copy of a copyrighted work, but not, for instance, to have a handy PDF of it to bring with you.
Oh, in the US if it was published before 1923 or you have permission from the author, go ahead. The first isn't protected, the second you are allowed.
There's also a question of Fair Use to make a copy, but that has a notoriously fuzzy boundary so I'm not going to attempt to talk about something I have limited and possibly misleading information about.