The PS3 system was unable to detect the PS one or PS2 game disc.
Remove the game disc from the system and clean the disc.
Please note that the only PS3 system compatible with PS2 game discs is the CECHC-series model with a 60GB Hard Disk Drive (HDD).
To find the model number and serial number of the PS3 system, locate the bar code sticker on the back of the system. Underneath the bar code you will see an 11-digit serial number followed by a model number beginning "CECH".