Попробуйте следующее:
<Grid VerticalAlignment="Center" HorizontalAlignment="Center">
<StackPanel Orientation="Horizontal">
<Button Content="1" Width="50" Height="23" Visibility="Collapsed"/>
<Button Content="2" Width="50" Height="23"/>
<Button Content="3" Width="50" Height="23" Visibility="Collapsed"/>
<Button Content="4" Width="50" Height="23"/>
</StackPanel>
</Grid>
Или это:
<Grid VerticalAlignment="Center" HorizontalAlignment="Center">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition Width="Auto"/>
</Grid.ColumnDefinitions>
<Button Grid.Column="1" Content="1" Width="50" Height="23" Visibility="Collapsed"/>
<Button Grid.Column="2" Content="2" Width="50" Height="23"/>
<Button Grid.Column="3" Content="3" Width="50" Height="23" Visibility="Collapsed"/>
<Button Grid.Column="4" Content="4" Width="50" Height="23"/>
</Grid>
Вы должны видеть кнопки по центру, но показывать только вторую и четвертую кнопку