I'm sorry to hear about that bad luck you had.
Depending on your operating system you might try special computer forums.
Companies invest a lot of money into destruction of data when they throw their hard drives into the trash. There are sophisticated applications to do that, as even five or six times overwritten data can still be recovered by the right person.
So, if it is so hard to destroy data, there may be the slight chance that not everything is lost.
I don't want to give you hopes, as I am not a computer specialist.
Just go out there, and try to get all the info, and you can at least say to yourself, that you did everything you could.
Regarding the back-up to disc: digital movies, for long term storage, are not being backed up to a burned disc, as those discs can sometimes detiorate in less than ten years. Become unreadable. So they back up digital movies... in analog film, storing the digital info on analog film.
So don't depend on discs alone. I'd rather say, get both back-up hard drives and discs.
I wish you good luck.