Did you format the hard drive in the ps3 game os allotting either 10gb or the rest of the disk space to Linux? If not then its under System...
Sounds like a bad iso. Either redownload and check the integrity of the file with a utility called sha1sum or check your existing file and hope it...
To get back to the game os, you need to hold the power button for 10 secs to shut down and then press the power button again but continue to hold...
Separate names with a comma.