if (window.Event) //
  document.captureEvents(Event.MOUSEUP); //

function nocontextmenu() //
{
   event.cancelBubble = true
   event.returnValue = false;

   return false;
}

function norightclick(e)   // 
{
   if (window.Event)   //
   {
      if (e.which == 2 || e.which == 3)
         return false;
   }
   else
      if (event.button == 2 || event.button == 3)
      {
         event.cancelBubble = true
         event.returnValue = false;
         return false;
      }

}

document.oncontextmenu = nocontextmenu;      // 
document.onmousedown = norightclick;      //