PHP basic problem

first of all I just want to say that I know absolutely nothing about PHP, so I just copied this thing and changed the values… It’s a simple mail form.

This is form.html:

<form method="post" action="sendmail.php">
  Email: <input name="email" type="text"><br><br>
  Message:<br>
  <textarea name="message" rows="8" cols="30"></textarea><br>
  <input type="submit" value="send">
  <input type="reset"  value="clear form">
</form>

And this is sendmail.php:

 <?php
  $email   = $_REQUEST['email'] ;
  $message = $_REQUEST['message'] ;   mail( "danulf@gmail.com", "Feedback Form Results",
    $message, "From: $email" );
  header( "Location: http://www.kirupa.com" );
?>

Now when I press the send button, it just opens the .php file in notepad… I’ve installed PHP 5.1.1 binarys on my computer, but I can’t get this to work! It’s really simple (I hope) I’ve tried the tutorial several times, and I’ve reinstalled PHP on my comp too, but it doesn’t work… :sleep:

Thankful for fast help!