Your approach is incorrect. You do not style menus and toolstrips using forecolor/backcolor.
Take a look at ToolStripProfessionalRenderer
Example on how to use this
public class MyToolStripRenderer : ToolStripProfessionalRenderer
{
/* override styling/drawing here */
}
MenuStrip strip = new MenuStrip();
strip.Renderer = new MyToolStripRenderer();
//this will set RenderMode to "Custom"
consider using this example on CodeProject as some research.
Better still, VBForums have loads of them, already implemented (in the usual Luna, Office, Windows, Visual Studio styles!)
http://www.vbforums.com/showthread.php?596563-100-Customizable-MenuStrip-ToolStrip-StatusStrip-including-common-presets
If you simply want to chaneg the colors...use Pondidum's answer! It involves less work!