Hi, from the information u give i really can't decide what the problem is with the disk. But if you want to recover the data, i think u may have a look at this data recovery software:
http://download.cnet.com/iCare-Data-Recovery-Free/3000-2248_4-75628752.html
It is an expert in data recovery and the operation is also quite simple. After installation the software will scan the disk to find the lost data. But if ur files u have to retrieve is large, the recovery will need a long time so plz be patient.
If u are not sure about the manual, visit here: http://freeware-recovery.blogspot. [...] overy.html u may find some useful information.
BTW, in case the software above dose not work, have a look at this: http://www.powerdatarecovery.com/ it is also a data recovery software.