Ipod can only sync about 10th of the songs and then encounter unknown error

Question

A bit of a back story:
So the problem started when my ipod classic 160gb started going funny on me, jumping songs and skipping others when i used it. so i decided to restore it. however, since then whenever i try and sync songs back into it, it will freeze- every time on a different song- and say that it could not sync the songs, giving a variety of different issues and errors:
"Itunes could not sync (name of song) to the ipod (ipod name) because the file cannot be read or written". alternatively, "...because an unknown error has occured (-50)".
"windows was unable to save all the dad for the file F:, the data has been lost. this error may be caused by a failure of your computer hardware or network connection. please try to save this file elsewhere"
and "The specified I/O operation on \Device\harddisk1\DR9\ was not completed before the time out period expired.",
"The Ipod (name of ipod) could not be synced. a duplicate filename was specified" and a few other varieties of these messages
I tried resetting the ipod,using different usb ports and plugs, restoring the ipod several times and reinstalling itunes but non helped..
I tried this solution:
http://support.apple.com/kb/TS1539 and the error-checking tool for windows
but also of no help
I then tried to add songs manually in chunks of about 100 and it worked until about 750 songs ish (out of 3,000), and then whatever song you try to add doesnt work....
I also tried to add photos and movies but it looks like its all a matter of size, as in if any more then the music equvelent of movies or videos will be uploaded it wont work but any less it would
any ideas?

Answer 1

I also used the diagnostic mode to check the hard disc situations, as explained here:
http://discussions.apple.com/thread.jspa?threadID=2623917&tstart=0
and got the folllowing results:
retracts:1
reallocs: 5704
pending sectors: 576
powerOn hours: 55
Start/Stops: 3976
temp current: 25C
Temp Min: 13C
Temp Max: 53C
so i think that means the hard drive is stuffed, which may explain the issue
is there anything i can still do?