Question : Problem: how to set external monitor as primary when option is dimmed

I know it can be done because I did it when I first purchased monitor!  But I disconnected the notebook (Asus A4000) from the monitor last week and now I can't get it to reconnect.
The monitor will work as extended desktop but the option to make it the primary monitor is not available
Running XP Pro.
Also, I've noticed that the F8 toggle on the keyboard is not activating
And i notice that the drop down box doesnt show the monitor name _ LG225WT.
Have reinstalled the drivers, rebooted a million times etc.
have set the notebook monitor to medium colour quality (i read this is necessary)
device manager and display setting screen shots attached
help!

Answer : Problem: how to set external monitor as primary when option is dimmed

So recapping do you understand what happened here?
You were basically looking at your laptop display through default monitor 2
 the reason>
When you changed the default monitor from one to two and then removed the # two
( secondary monitor) which of course the laptop went black and that screwed it all up.
 windows was identifying with default monitor two nolonger there.
Installing the drivers put them onto monitor two as well.
So remember to put the displays back to their correct positions before unplugging this secondary monitor.
You are most welcome always happy to help out !!!!  :)