So basicly, if I understand this all.

If I restore the backup given to me on the this thread with Backupmenu it'll just restore the rootfs and the other one, but it doesn't remove the kernels ( as they are in /boot/ ).

Thanks Ade and Pali for the information !!

Now I have a qeustion about nitdroid, isn't that one under a different location? ( /and/ ) instead of /boot/ ?