I have (slightly) modified one of emanual's tutorials.
It presents a menu (you can add/change) the entries
it then calls a system command and outputs the results to the 'command' window.
the command window size is fixed by the skin you are using - don't know how to make it bigger - you can play!!

download the rar
create a directory called smallutils inside
/usr/lib/enigma2/python/Plugins/Extensions
put the 3 files in that directory
chmod 644
restart gui (this puts the plugin into the plugins menu)

modify the code as you want:-
to do that, you edit the plugin.py file
delete the two .pyo files in the /usr/lib/enigma2/python/Plugins/Extensions/smallutils directory
restart gui