For mounting, you will need to adjust your entrie(s) in fstab. Something like:
/dev/hdxx /mnt/files ext2 users,noauto,rw 0 0
Could be what you need, but you would obviously need to tailor it, and add/remove things in the options section. man mount and man fstab will give you a better idea of what's going on there.
As for shutting down, I just do a 3 fingered salute. That does not require root priviledges. Of course if you want to shutdown and halt, you can still do the 3 finger, but need to adjust in /etc/inittab what the entry says for the 3 fingered. Make it -h rather than -r for halt rather than reboot respectively.