Further to my previous post, if you do not have it installed already, I recommend that you install the easy-to-use and powerful text editor vim.
I much prefer it to kate (kde) or gedit (gnome) or vi or any other editor.
There is a good vim tutorial here:
Type in the terminal as ordinary user ($):
su (press Enter)
Now type your root password (nothing will be displayed, by the way, so make sure that your typing is correct) and press Enter.
You should now be logged into the terminal as superuser (root) #.
Type the following:
apt-get install vim
If you are using Ubuntu then type:
sudo apt-get install vim
(give your Ubuntu password when prompted).