Let's be honest - if you gave someone a BlueRay disk *today*, there's a pretty good chance they'd have to go hunting around to find some hardware to read it. 1,000 years from now, you'd have to:
- Set up the appropriate laser hardware to scan the physical medium at the appropriate resolution, frequency, etc, while not going so high power that you damage the disc.
- Translate the physical pits on the disc to a bitstream.
- Translate the bitstream as a filesystem data.
- Translate the contents of the files (anyone still have a copy of Word 95?)
This technology is probably fantastic on a scale of a few decades, so long as you're careful about which file formats you pick, but if you're serious about centuries or more you'd probably have to stick to something that requires no technology to read, like engravings on glass or non-corrosive metals.
(For extra fun, just imagine the fun in a few centuries when amateur archeologists try to figure out these funny markings that turn out to be QR codes
)