Firstly, that's an iPod Classic, not an iPod Video, the two are similar bit differ greatly.
This means you're running a third party, unsupported bootloader (emCORE), and an unsupported Rockbox binary.
Secondly, if your disk is damaged in such a way that your host OS refuses to mount it, even after an attempted recovery from within emCORE, from the fallback image, it is almost a certainty that nothing short of a new disk is going to fix it.
The guys over at Freemyipod have a tool that can recover badly damaged, yet still functional, disks - but it can take months (yep, months, really) to run a single pass of this tool, and several passes may be required.
[Saint]