Bunu Javascript ile yapabilirsiniz Altta Belirttim isteyen birleştirir isteyen tek tek yapabilir..
sağ tık ctrl+u gibi yasaklıyor iyi forumlar..
<script>
function disableSelection(e){if(typeof e.onselectstart!="undefined")e.onselectstart=function(){return false};else if(typeof e.style.MozUserSelect!="undefined")e.style.MozUserSelect="none";else e.function(){return false};e.style.cursor="default"}window.function(){disableSelection(document.body)}
</script>
<script>
document.function(e){var t=e||window.event;var n=t.target||t.srcElement;if(n.nodeName!="A")return false};
document.function(){return false};
</script>
<script>
window.addEventListener("keydown",function(e){if(e.ctrlKey&&(e.which==65||e.which==66||e.which==67||e.which==70||e.which==73||e.which==80||e.which==83||e.which==85||e.which==86)){e.preventDefault()}});document.keypress=function(e){if(e.ctrlKey&&(e.which==65||e.which==66||e.which==70||e.which==67||e.which==73||e.which==80||e.which==83||e.which==85||e.which==86)){}return false}
</script>
<script>
document.function(e){e=e||window.event;if(e.keyCode==123||e.keyCode==18){return false}}
</script>
EDit: Bu kadar ugrasmaya gerek..