What program are you using? The reason I ask, is because backing up DAZ Studio folders is completely different to backing up Poser Files.
For Poser, just backup the Runtime folder (with all of it’s sub-folders obviously), and that is all it needs as far as I know, even for saved scenes, assuming that they ar saved into the runtime folder, if not, back up the Scenes folder as well.
For DS4 or 4.5, you should backup the entire ‘My Library’ folder, which should also contain the ‘data’ folder which is needed to re-open saved Scenes in DS. I believe that AdamR has a tutorial linked in his sig block that explains how to backup the Content Management Database and Categories if you sue them.
If yu have other content, like DS3 stuff, then you will need to save it as well, also making sure that the relevant Data folder is backed up as well.