<Grid>

    <Rectangle Name="Rectangle1" MouseEnter="ColorChangeMouseEvent" MouseLeave="ColorChangeMouseEvent" Margin="198,17,0,0" Height="88" 

VerticalAlignment="Top" HorizontalAlignment="Left" Width="100">

        <VisualStateManager.VisualStateGroups>

            <VisualStateGroup Name="MouseStates">

                <VisualState Name="BlueState">

                    <Storyboard>

                        <ColorAnimation To="Blue" Storyboard.TargetName="rectBrush" Storyboard.TargetProperty="Color"/>

                    </Storyboard>

                </VisualState>

                <VisualState Name="OrangeState">

                    <Storyboard>

                        <ColorAnimation To="Orange" Storyboard.TargetName="rectBrush" Storyboard.TargetProperty="Color"/>

                    </Storyboard>

                </VisualState>

                <VisualStateGroup.Transitions>

                    <VisualTransition To="BlueState" GeneratedDuration="0:0:2"/>

                    <VisualTransition To="OrangeState" GeneratedDuration="0:0:2">

                    </VisualTransition>

                </VisualStateGroup.Transitions>

            </VisualStateGroup>