function disableSelection(target){
if (typeof target.onselectstart!="undefined") //IE route
	target.onselectstart=function(){return false}
else if (typeof target.style.MozUserSelect!="undefined") //Firefox route
	target.style.MozUserSelect="none"
else //All other route (ie: Opera)
	target.onmousedown=function(){return false}
target.style.cursor = "default"
}

<!--

//Disable right mouse click Script
//By Maximus (maximus@nsimail.com) w/ mods by DynamicDrive
//For full source code, visit http://www.dynamicdrive.com

var message="Sag tus kapali\nCtrl+Right click disabled!";

///////////////////////////////////
function clickIE4(){
if (event.button==2){
alert(message);
return false;
}
}

function clickNS4(e){
if (document.layers||document.getElementById&&!document.all){
if (e.which==2||e.which==3){
alert(message);
return false;
}
}
}

if (document.layers){
document.captureEvents(Event.MOUSEDOWN);
document.onmousedown=clickNS4;
}
else if (document.all&&!document.getElementById){
document.onmousedown=clickIE4;
}
var isnn,isie
if(navigator.appName=='Microsoft Internet Explorer') //check the browser
{  isie=true }

if(navigator.appName=='Netscape')
{  isnn=true }


function right(e) //to trap right click button 
{
	if (isnn && (e.which == 3 || e.which == 2 ))
		return false;
	else if (isie && (event.button == 2 || event.button == 3)) 
	{
		alert("Ctrl tusu ve Sag tus kapali\nCtrl+Right click disabled");
		return false;
	}
		return true;
}

function key(k)   
{
	if(isie) {
		if(event.keyCode==17 || event.keyCode==18 || event.keyCode==93)
		 {
			alert("Ctrl tusu ve Sag tus kapali\nCtrl+Right click disabled") 
			return false;
		 } 
		  
	}

 
}

if (document.layers) window.captureEvents(Event.KEYPRESS);  
if (document.layers) window.captureEvents(Event.MOUSEDOWN);
if (document.layers) window.captureEvents(Event.MOUSEUP);
//document.onkeydown=key;  
//document.onmousedown=right;
//document.onmouseup=right;
//window.document.layers=right;
//document.oncontextmenu=new Function("alert(message);return false")
disableSelection(document.body)
// -->