Really nothing you can do except be sensible. Don't move them while they're powered on, and keep them in a mild temperature and relative humidity environment comfortable for a human. That's about it.
Just have a backup. And a backup of your backup. That way you don't have to worry about it.
Yes, optical drives can just "go bad" while sitting. Even if not the laser, many of the mechanical parts can age and fail.
There is no "set it and forget it" medium in existence. Multiple copies, in multiple locations and if possible on different media types.