How much troubleshooting have you done with this? I encountered this error with one of my Blu-ray discs here. I took it out of the drive and noticed it was fairly dirty, so I cleaned it. It still didn't work, but I also noticed some small barely noticable dents in the read surface of the disc. When I put it in my PS3, it failed to read there with an 80029940 error. It turns out the disc had been damaged.
When I put my Scott Pilgrim blu-ray in, it played just fine.