I am not entirely sure what you mean, but perhaps what you need is to set the ProgressBar's IsIndeterminate property to false. If that does not work, then please give us some code to help you further!
EDIT:
The animation is part of the Windows Aero style and some designer was payed big bucks to ... err desgin it! So you cannot simply remove the animation using a property. You can alter the visual appearance of existing ProgressBars by editing their controltemplate. Below is the entire controltemplate of the WPF ProgressBar. Mind: you need all the Resources, the xmlns reference to Window.Themes and you must set a reference to the PresentationFramwork.Aero dll. I inserted a comment where you can make the change.
Change the color FF000000 to 00000000 on the second and third gradientstops and the white glow disappears. I tried to implement a trigger that will show the animation at first, but stops it when Value==Maximum, but I failed. Someone else?
<Window x:Class="BlandProgressBarSpike.Window1"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:Microsoft_Windows_Themes="clr-namespace:Microsoft.Windows.Themes;assembly=PresentationFramework.Aero"
Title="Window1" Height="300" Width="300"
Loaded="Window_Loaded">
<Window.Resources>
<LinearGradientBrush x:Key="ProgressBarBackground" EndPoint="1,0" StartPoint="0,0">
<GradientStop Color="#BABABA" Offset="0"/>
<GradientStop Color="#C7C7C7" Offset="0.5"/>
<GradientStop Color="#BABABA" Offset="1"/>
</LinearGradientBrush>
<LinearGradientBrush x:Key="ProgressBarBorderBrush" EndPoint="0,1" StartPoint="0,0">
<GradientStop Color="#B2B2B2" Offset="0"/>
<GradientStop Color="#8C8C8C" Offset="1"/>
</LinearGradientBrush>
<LinearGradientBrush x:Key="ProgressBarGlassyHighlight" EndPoint="0,1" StartPoint="0,0">
<GradientStop Color="#50FFFFFF" Offset="0.5385"/>
<GradientStop Color="#00FFFFFF" Offset="0.5385"/>
</LinearGradientBrush>
<LinearGradientBrush x:Key="ProgressBarTopHighlight" EndPoint="0,1" StartPoint="0,0">
<GradientStop Color="#80FFFFFF" Offset="0.05"/>
<GradientStop Color="#00FFFFFF" Offset="0.25"/>
</LinearGradientBrush>
<!-- This produces the whitish,moving glow-->
<LinearGradientBrush x:Key="ProgressBarIndicatorAnimatedFill" EndPoint="0,0" StartPoint="-100,0" MappingMode="Absolute">
<GradientStop Color="#00000000" Offset="0"/>
<GradientStop Color="#FF000000" Offset="0.4"/>
<GradientStop Color="#FF000000" Offset="0.6"/>
<GradientStop Color="#00000000" Offset="1"/>
</LinearGradientBrush>
<LinearGradientBrush x:Key="ProgressBarIndicatorDarkEdgeLeft" EndPoint="1,0" StartPoint="0,0">
<GradientStop Color="#0C000000" Offset="0"/>
<GradientStop Color="#20000000" Offset="0.3"/>
<GradientStop Color="#00000000" Offset="1"/>
</LinearGradientBrush>
<LinearGradientBrush x:Key="ProgressBarIndicatorDarkEdgeRight" EndPoint="1,0" StartPoint="0,0">
<GradientStop Color="#00000000" Offset="0"/>
<GradientStop Color="#20000000" Offset="0.7"/>
<GradientStop Color="#0C000000" Offset="1"/>
</LinearGradientBrush>
<RadialGradientBrush x:Key="ProgressBarIndicatorLightingEffectLeft" RelativeTransform="1,0,0,1,0.5,0.5" RadiusX="1" RadiusY="1">
<GradientStop Color="#60FFFFC4" Offset="0"/>
<GradientStop Color="#00FFFFC4" Offset="1"/>
</RadialGradientBrush>
<LinearGradientBrush x:Key="ProgressBarIndicatorLightingEffect" EndPoint="0,0" StartPoint="0,1">
<GradientStop Color="#60FFFFC4" Offset="0"/>
<GradientStop Color="#00FFFFC4" Offset="1"/>
</LinearGradientBrush>
<RadialGradientBrush x:Key="ProgressBarIndicatorLightingEffectRight" RelativeTransform="1,0,0,1,-0.5,0.5" RadiusX="1" RadiusY="1">
<GradientStop Color="#60FFFFC4" Offset="0"/>
<GradientStop Color="#00FFFFC4" Offset="1"/>
</RadialGradientBrush>
<LinearGradientBrush x:Key="ProgressBarIndicatorGlassyHighlight" EndPoint="0,1" StartPoint="0,0">
<GradientStop Color="#90FFFFFF" Offset="0.5385"/>
<GradientStop Color="#00FFFFFF" Offset="0.5385"/>
</LinearGradientBrush>
<Style x:Key="BlandStyle" TargetType="{x:Type ProgressBar}">
<Setter Property="Foreground" Value="#01D328"/>
<Setter Property="Background" Value="{StaticResource ProgressBarBackground}"/>
<Setter Property="BorderBrush" Value="{StaticResource ProgressBarBorderBrush}"/>
<Setter Property="BorderThickness" Value="1"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type ProgressBar}">
<Grid SnapsToDevicePixels="true" x:Name="Background">
<Rectangle Fill="{TemplateBinding Background}" RadiusX="2" RadiusY="2"/>
<Border Margin="1" Background="{StaticResource ProgressBarGlassyHighlight}" CornerRadius="2"/>
<Border Margin="1" Background="{StaticResource ProgressBarTopHighlight}" BorderBrush="#80FFFFFF" BorderThickness="1,0,1,1"/>
<Rectangle Margin="1" x:Name="PART_Track"/>
<Decorator HorizontalAlignment="Left" Margin="1" x:Name="PART_Indicator">
<Grid x:Name="Foreground">
<Grid.RowDefinitions>
<RowDefinition/>
<RowDefinition/>
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition MaxWidth="15"/>
<ColumnDefinition Width="0.1*"/>
<ColumnDefinition MaxWidth="15"/>
</Grid.ColumnDefinitions>
<Rectangle x:Name="Indicator" Fill="{TemplateBinding Foreground}" Grid.ColumnSpan="3" Grid.RowSpan="2"/>
<Rectangle x:Name="Animation" Fill="{TemplateBinding Foreground}" Grid.ColumnSpan="3" Grid.RowSpan="2">
<Rectangle.OpacityMask>
<MultiBinding>
<MultiBinding.Converter>
<Microsoft_Windows_Themes:ProgressBarHighlightConverter/>
</MultiBinding.Converter>
<Binding Source="{StaticResource ProgressBarIndicatorAnimatedFill}"/>
<Binding Path="ActualWidth" ElementName="Background"/>
<Binding Path="ActualHeight" ElementName="Background"/>
</MultiBinding>
</Rectangle.OpacityMask>
</Rectangle>
<Rectangle Margin="1,1,0,1" x:Name="LeftDark" Fill="{StaticResource ProgressBarIndicatorDarkEdgeLeft}" RadiusX="1" RadiusY="1" Grid.RowSpan="2"/>
<Rectangle Margin="0,1,1,1" x:Name="RightDark" Fill="{StaticResource ProgressBarIndicatorDarkEdgeRight}" RadiusX="1" RadiusY="1" Grid.Column="2" Grid.RowSpan="2"/>
<Rectangle x:Name="LeftLight" Fill="{StaticResource ProgressBarIndicatorLightingEffectLeft}" Grid.Column="0" Grid.Row="2"/>
<Rectangle x:Name="CenterLight" Fill="{StaticResource ProgressBarIndicatorLightingEffect}" Grid.Column="1" Grid.Row="2"/>
<Rectangle x:Name="RightLight" Fill="{StaticResource ProgressBarIndicatorLightingEffectRight}" Grid.Column="2" Grid.Row="2"/>
<Border x:Name="Highlight1" Grid.ColumnSpan="3" Grid.RowSpan="2" Background="{StaticResource ProgressBarIndicatorGlassyHighlight}"/>
<Border x:Name="Highlight2" Grid.ColumnSpan="3" Grid.RowSpan="2" Background="{StaticResource ProgressBarTopHighlight}"/>
</Grid>
</Decorator>
<Border BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" CornerRadius="2"/>
</Grid>
<ControlTemplate.Triggers>
<Trigger Property="Orientation" Value="Vertical">
<Setter Property="LayoutTransform" TargetName="Background">
<Setter.Value>
<RotateTransform Angle="-90"/>
</Setter.Value>
</Setter>
<Setter Property="LayoutTransform" TargetName="PART_Track">
<Setter.Value>
<RotateTransform Angle="90"/>
</Setter.Value>
</Setter>
<Setter Property="LayoutTransform" TargetName="PART_Indicator">
<Setter.Value>
<RotateTransform Angle="90"/>
</Setter.Value>
</Setter>
<Setter Property="LayoutTransform" TargetName="Foreground">
<Setter.Value>
<RotateTransform Angle="-90"/>
</Setter.Value>
</Setter>
</Trigger>
<Trigger Property="IsIndeterminate" Value="true">
<Setter Property="Visibility" TargetName="LeftDark" Value="Collapsed"/>
<Setter Property="Visibility" TargetName="RightDark" Value="Collapsed"/>
<Setter Property="Visibility" TargetName="LeftLight" Value="Collapsed"/>
<Setter Property="Visibility" TargetName="CenterLight" Value="Collapsed"/>
<Setter Property="Visibility" TargetName="RightLight" Value="Collapsed"/>
<Setter Property="Visibility" TargetName="Indicator" Value="Collapsed"/>
</Trigger>
<Trigger Property="IsIndeterminate" Value="false">
<Setter Property="Fill" TargetName="Animation" Value="#80B5FFA9"/>
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</Window.Resources>
<StackPanel>
<ProgressBar Style="{StaticResource BlandStyle}" Value="{Binding Progress}" Height="30"
Minimum="0" Maximum="100"/>
</StackPanel>
</Window>