  <Button Margin="20">
    <!-- Button Content -->
    <DockPanel Width="200" Height="180">
      <Label DockPanel.Dock="Top" HorizontalAlignment="Center">Click Me!</Label>
      <Border Background="Black" BorderBrush="Yellow" BorderThickness="2" 
        CornerRadius="2" Margin="5">
        <MediaElement Source="media/wpf.wmv" Stretch="Fill" />
      </Border>
    </DockPanel>
  </Button>