If you are running KDE (AKA the "Advanced Desktop" - see http://wiki.eeeuser.com/howto:getkde
) on the stock Xandros OS then you can just R-click your desktop, Create New ... Link to application.
General Tab: Click on the blue gear Icon, and choose a more suitable icon, and then name it "External_Monitor" instead of just "Link to application".
Application Tab: In the Command box, put your command.
You now have a new desktop icon that'll do what you want with one click.
You can play with this new icon by R-clicking it and choosing "Properties".
If it annoys you by being on your desktop, drag it somewhere else. It needs to keep its name as something.desktop
If you did
want it to run in a terminal, under the Application Tab, Advanced Options, there's the option to "Run in terminal".
If you are not running KDE, I strongly suggest you install it: it is highly
customisable, which is one of the many reasons I love it.