[ubuntu] Problem upgrading from 12.04lts to 12.10

Hello everyone,

My system:Acer 5733,i3,6gb,600gb.
It came with windows7. I downloaded wubi-ubuntu12.04lts.

The problem: Using "Update Manager" i tried to upgrade from 12.04 to 12.10.
A box opened called "Distribution Upgrade" with a list of six tasks for it to do.
It did the first task "Preparing to upgrade"and gave it a green tick.
During the second task "Setting new software channels" it stopped and gave the following error:

{screenshot here}





There is about 70gb of free space on the partition I use for Linux. I don't know what " Disk '/' " means.
I'm a beginner when it comes to understanding Linux so if if anyone has any suggestions I'd be grateful.

thanks
paul