Recabar información del equipo en windows

WMI: Windows Management Instrumentation http://msdn.microsoft.com/en-us/library/windows/desktop/aa394586(v=vs.85).aspx

static void MostrarTodo(StringBuilder sb, string cad){
 ObjectQuery query = new ObjectQuery("Select * from " + cad);
 XmlOpen(sb,1,cad);
 ManagementObjectSearcher mos = new ManagementObjectSearcher(query);
 if(mos!=null){
  ManagementObjectCollection moc = mos.Get();
  if(moc != null){
   foreach (ManagementObject mo in moc) {
    PropertyDataCollection pdc = mo.Properties;
    if(pdc != null){
     foreach (PropertyData pd in pdc) {
      AppendProperty(sb, pd);
     }
    }else{
     sb.AppendLine("");
    }
   }
  }else{
   sb.AppendLine("");
  }
 }else{
  sb.AppendLine("");
 }
 XmlClose(sb,1,cad);
}

Se le llamaría con:

MostrarTodo(sb, "Win32_Desktop");
MostrarTodo(sb, "Win32_DesktopMonitor");
MostrarTodo(sb, "Win32_OperatingSystem");
MostrarTodo(sb, "Win32_StartupCommand");

   
MostrarTodo(sb, "Win32_LogicalDisk");
MostrarTodo(sb, "Win32_MappedLogicalDisk");
MostrarTodo(sb, "Win32_DiskDrive");

MostrarTodo(sb, "Win32_NetworkAdapter");
MostrarTodo(sb, "Win32_NetworkAdapterConfiguration");