$(document).ready(function(){

   $("#enter") . mouseover( function() {
      $(this).attr('src', 'images/buttons/Enter-over.jpg');
   });
   
   $("#enter") . mouseout( function() {
      $(this).attr('src', 'images/buttons/Enter.jpg');
   });
   
   $("#enter") . click( function() {
      $.get("set_language.php", { lang: $("#lang") . val() },
         function(data){
            window.location.href = "home.php";
         });    
   }); 
   
});