My whole system is read-only so I can't even connect to WiFi (needs authentication).
So I went into the terminal:
sudo su
nautilus
It sat there for about 20 seconds with no output then it had a bunch of errors then nautilus started.
I used that to go into /usr/shared/applications
(or whatever) to launch "Disks" and it says nothing about being read-only.
So Im running on the terminal now as I can't use anything that writes settings or anything to the HDD.