Changing ownership of read-only file system

Solution 1:

Remount the partition (or disc) but this time with rw (read, write) settings. Should be something like this:

sudo mount -o rw,remount /"Untitled 1"

Ok, so after a lot of looking around and conferring with my friends, this is what worked for me.

My external hard drive has a journaled file system (hfs+). I don't quite care what that means but I had to "disable journaling".

For this I had to connect my hdd to my macbook and run the following command in it's terminal

sudo /usr/sbin/diskutil disableJournal /Volumes/name-of-my-external-hdd

That worked and my hdd is now read AND write enabled!!

Hope this helps someone in the future! :)