I have successfully gained access to my data and recovered everything
I had some small setbacks at mounting the image but I solved it specifying the partition offset.
In fact those few damaged blocks I gave up recovering I believe are not involved with any of my data but are all system based.
Code:
lubuntu@lubuntu:~$ sudo mount -o loop,offset=1048576 /media/lubuntu/Storage/HddSuper/prova/image /media/lubuntu/Storage/HddSuper/prova/mountpoint
Windows is hibernated, refused to mount.
Did not find any restart pages in $LogFile and it was not empty.
The file system wasn't safely closed on Windows. Fixing.
Falling back to read-only mount because the NTFS partition is in an
unsafe state. Please resume and shutdown Windows fully (no hibernation
or fast restarting.)
Could not mount read-write, trying read-only
Read-only was more that enough
It was April 21; a five month adventure where I learned many things and yet merely scratched the surface of DR. It was enough to have an idea of how complex is a HDD, how much time and effort you need to make a recovery and to build the necessary experience to be a DR person. I completely understand now why their services are so (relatively) expensive. This is what I got for not having backuped my data regularly, and I've been very lucky my HDD was in a still good enough state I could access it with a few commands. It was a good lesson.
A special thank goes to maximus and especially fzabkar who assisted me from the beginning until the end and everyone who took part in this discussion. Thank you guys!
Another thing I learned: stay away form Seagate. And speaking of which, what HDD brand would you guys advice these days?
I think I will try to run a CHKDSK with Windows and see if it is able to make the image bootable again, although I do not hold out much hope for it, and I will likely try to regenerate the HDD and use it for unimportant stuff; so I might post again for advice.