I had bad blocks on my iPod classic 120gb. I was told to trash it and by a certified technician but I wouldn’t give up. I tried reformating at least 50 times. My iPod would restore and show up in iTunes no problem but I couldn’t copy more than 2gb of data before iTunes would hang.
I also tried reformating the iPod with Disk Utility. I was able to format but not with
zero out data selected (recommended for fixing bad blocks). I even tried changing the partition map through terminal but was unsuccessful — via Mac OS X Hints