To expand on Shawn Mclean's answer, one of the great capabilities of WPF is the ability to leverage the behavior of a control while completely changing the look of that control. If you want to create an image that behavior just like a button (complete with click events, command binding, default button assignment, etc.) you can place an image in a button control and restyle that button to remove the button "chrome". This will give you the nice API of a button with the look you desire. You can reuse this style and this approach will reduce the need to create event handlers in your code behind if you have commands to bind to your new image buttons.
Creating such a style is pretty easy. Simply create a new style resource with a named key in a resource and assign this resource to the Style property of your buttons. Here is an example I threw together:
<Window
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
x:Class="ButtonStyleTestApp.MainWindow"
x:Name="Window"
Title="MainWindow"
Width="640" Height="480">
<Window.Resources>
<Style x:Key="NoChromeButton" TargetType="{x:Type Button}">
<Setter Property="Background" Value="Transparent"/>
<Setter Property="BorderThickness" Value="1"/>
<Setter Property="Foreground" Value="{DynamicResource {x:Static SystemColors.ControlTextBrushKey}}"/>
<Setter Property="HorizontalContentAlignment" Value="Center"/>
<Setter Property="VerticalContentAlignment" Value="Center"/>
<Setter Property="Padding" Value="1"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type Button}">
<Grid x:Name="Chrome" Background="{TemplateBinding Background}" SnapsToDevicePixels="true">
<ContentPresenter HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}" Margin="{TemplateBinding Padding}" RecognizesAccessKey="True" SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}" VerticalAlignment="{TemplateBinding VerticalContentAlignment}"/>
</Grid>
<ControlTemplate.Triggers>
<Trigger Property="IsEnabled" Value="false">
<Setter Property="Foreground" Value="#ADADAD"/>
<Setter Property="Opacity" TargetName="Chrome" Value="0.5"/>
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</Window.Resources>
<Grid x:Name="LayoutRoot" Background="#FF44494D">
<Button Style="{DynamicResource NoChromeButton}" Click="ButtonClicked" >
<Image Source="Desert.png" Stretch="None"/>
</Button>
</Grid>
</Window>
与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…