I think another possibility could be
you make 3 panel diffrent szie 800x600, 1024x758, 645x350 (i dont know it exactly)
but then you write something like

if (video_mode == 8) // 1024x758 resolution
{
the_panel.visible = on;
}
else
{
visible off
}
if(video_mode == 7) // 800x600 resolution
{
the_panle2.visible = off;
}
else......

I hope you know what I mean