ASP.NET MVC Routing to start at html page

I am using IIS 6. I think my problem is that I don't know how to route to a non controller using the routes.MapRoute.

I have a url such as example.com and I want it to serve the index.htm page and not use the MVC. how do I set that up? In IIS, I have index.htm as my start document and my global.asax has the standard "default" routing, where it calls the Home/Index.

    public static void RegisterRoutes(RouteCollection routes)
    {
        routes.IgnoreRoute("{resource}.axd/{*pathInfo}");
        routes.MapRoute(
            "Default",                                              // Route name
            "{controller}/{action}/{id}",                           // URL with parameters
            new { controller = "Home", action = "Index", id = "" }  // Parameter defaults
        );

    }

I added this:

    protected void Application_BeginRequest(object sender, EventArgs e)
    {
        if (Context.Request.FilePath == "/") Context.RewritePath("index.htm");
    }

it works. But is this the best solution?