Monitor config.

[bugsy]

I have recently formated my laptop installed XP pro. and conected up my external monitor. I found that the driver for my video adaptor needed upgrading as it would not allow dual monitors - so went to Toshiba to find what Video card i had built in and down loaded the recommended driver. Hey presto it worked two monitors, however i can not select my external monitor as my default can anyone help? I can adjust the screen positions, sizes etc but the 'select as default' box is greyed out.