I found this script and made a menu shortcut to shutdown my netbook screen and fix the resolution for my external monitor. Here are both commands:
# Close my netbook screen and adjust resolution of ext. monitor # Labels can be taken from "grandr" command xrandr --output LVDS1 --off & xrandr --output VGA1 --mode "1680x1050" &
Also, I often need to administrate the network connections as root (ex : to add a permanent static configuration to the wired card).