The ip address of the remote (broken) machine is 192.168.10.7, according to the display when I boot in as root with networking enabled.
But, when I use the command you gave:
... it comes back with "Connection refused".
ssh -X -l ogp 192.168.10.7
And the same happens if I use -Y instead.
(Clearly, ogp is my login and 192.168.10.7 is the ip address.)
I can ping 192.168.10.7 from the working machine just fine - lots of responses.
On the broken machine, I have logged in from the root command line, and typed "mount", as you suggested. It produced a screenful of information, but I can't see which bit you mean by 'post the line about "/"'. If you mean the various mounts listed, they are as follows:
There are more ... do you want the rest?
/dev/sda7 on / type ext3
tmfps on /lib/init/rw type tmpfs
proc on /proc type proc
sysfs on /sys type sysfs
varrun on /var/run type tmpfs