<p>I am progamatically creating a SharePoint site using </p>

<pre><code>SPWeb spWeb = spSite.AllWebs.Add(...);
</code></pre>

<p>What code do I need run to set the spWeb to turn off the "Show pages in navigation" option?</p>

<p><strong>Answer:</strong></p>

<pre><code>publishingWeb.IncludePagesInNavigation = false;
</code></pre>

Wasn't sure myself but I was able to locate
this
:
Modifying navigation is another common
  branding task since it affects what
  users can see and how they can proceed
  through a site hierarchy. The
  Microsoft.SharePoint.Publishing
  namespace exposes several classes that
  target the Publishing site
  infrastructure, such as PublishingWeb
  and PublishingPage. Using these
  classes, we can easily modify
  navigation for each site. If you want
  a child Web to display as a root level
  site in global navigation, first turn
  off inheritance from the parent site,
  like so:
```
```
publishingWeb.InheritGlobalNavigation = false;
```
```
You might also want to hide all site
  pages from global navigation. Setting
  IncludePagesInNavigation to false
  hides all pages in the site,
  regardless of whether the
  PublishingPage.IncludeInGlobalNavigation
  property is set to true
```
```
// do not show pages in navigation
publishingWeb.IncludePagesInNavigation = false;
```
```
If you are dealing with default sites
  that don't inherit from PublishingWeb,
  it's still possible to hide these
  sites from the global navigation bar.
  For example, if you create a site
  collection using the collaboration
  portal template and want to exclude
  the News site from global navigation,
  add that site to the
  __GlobalNavigationExcludes property of the site:
```
```
string globalNavExcludes = String.Empty;
SPWeb webSite = MSDNSiteCollection.RootWeb;
// _GlobalNavigationExcludes property contains a delimited string of 
// GUIDs identifying the Id of each site to be excluded from global
// navigation

if (webSite.AllProperties.ContainsKey("__GlobalNavigationExcludes")) {
  globalNavExcludes = 
    webSite.AllProperties["__GlobalNavigationExcludes"].ToString();
}

SPWeb newsSite = MSDNSiteCollection.AllWebs["News"];
// string is delimited "{GUID};{GUID};",
// use format code B to convert to string
globalNavExcludes += String.Concat(currentWeb.ID.ToString("B"), ";");

webSite.AllProperties["__GlobalNavigationExcludes"] = globalNavExcludes;
webSite.Update();
```
```
Adding navigation nodes directly to an
  SPNavigationNodeCollection is a good
  way to display only the nodes you want
  as well as to group nodes and links to
  external sites. Figure 10 shows how to
  add an internal link, external link,
  and a heading to the global navigation
  bar. This example addresses some of
  the properties of the SPNavigation
  class that affect whether the link
  opens in a new window and how to
  handle empty URLs.