I have seen too many drives that work with the OS up but can't boot or be seen by the method you noted.
So far, we find that cleaning the CD/DVD lens and media might recover a few but after that we try a new ODD (optical disc drive.)
Only the new tech digs in their heels. Or owners.
So following a corrupt hard drive, i've bought a new toshiba 500GB HD for my MBP (2009). I've got the original Mac OSX 10.5.6 install disc but when i attempt to boot from cd (holding 'c' key) it fails to load the disc. When i put a working HD in the machine the cd drive works with other cds but doesn't register the install disc or the apps install disc.
I've tried creating a partition on my new HD using disk utility from booting up an old HD but still no change.
Strange thing is that when the original HD went currupt i couldn't get the computer to boot from install disks and put this down to the corrupt HD....obviously not. I even tried a number of different discs with different versions of osx but to no avail.
So i'm not convinced that its a problem with the disc or the disc drive or the hard drive....i'm running out of ideas!...heeeelp!