This just happened to me last week on my 60gb ntsc us ps3(fw 3.15) while playing god of war collection. the game froze the ps3, which then had to be turned off with the main power switch. After the reboot, blu-ray discs will not work, only ps1 and ps2. Lucky for me I bought a spare blu ray laser and assembly about 2 months after buying the ps3 just to be safe(because I knew what WILL happen eventually). Swapped the lasers and I'm good to go again until the next time.....
PS2 v9 NTSC 750gb HDD(SATA modded NA)
PS2 v9 NTSC 40gb official HDD & NA
PS3 60gb NTSC b/c
Original Xbox w/ 1TB HDD (SATA modded)
WII w/ 250GB HDD(bannerbombed)
Xbox 360 Xenon Jtag