I read it too fast ...
Anyway I recovered most of the windows hdd.
To be safe now, I use another hdd, and try to install from the cds.
When installing lmce, I have an error after specifying the kubuntu iso location :
"can't cache kubuntu live CD"
Could it come from a too small swap partition ? (default size, and I have 1G of Ram)
I really have no idea why it displays this. (the ISO is ok, checked with MD5)
Any clue ?
So I tried again with the DVD, but it's not as flexible.