I have done many fsck attempts but it fails.Anyway, I found the solution, it's a little nice tool called dd_rescue which manages to copy the whole partition even when it encounters I/O errors caused by bad blocks.The output is a file which is the image of the hard disk with the holes from the bad blocks in it but I hope repairable with fsck after all !
http://www.garloff.de/kurt/linux/ddrescue/
edit: Yes, I managed to copy 28 GB of data with dd_rescue, then repaired the image with fsck.reiserfs and finally mounted it with mount -t reiserfs -o loop (must have kernel enebled for loopback device)
May I mention I am ...*happy* ?