function nomenu() 
{
event.cancelBubble = true;
event.returnValue = false;
return false;
}

function noclick(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 = nomenu;  
document.onmousedown = noclick;