For the shutdown, the computer was on a black screen, nothing written, nothing noticed, except that... it was still power on. Now it works.
For the SD card, my problem is not about manual mounting, but my problem is with automount (like the problem i have with the large fat32 partition -see my other post in this topic-, the same problem, but not the same reasons). I plug the card, nothing happens. I could use 'mount', by as i said in my other post, BUT in 2008, and in a userfriendly distro, i want to avoid it when it's not necessary. Typically in this case... Anyway, i'll give you the dmesg. Tomorrow if i've got the time (right now i'm with my mac), else later... going in vacations, yes !