I've made a few changes to the form, and then if you use the PHP code at the bottom on the actin page of the form it will mail to whoever is selected
<form name="form1" method="post" action="">
<p>Your Name:
<input name="Your Name:" type="text" id="Your Name:">
</p>
<p>Your Email:
<input name="Your Email:" type="text" id="Your Email:">
</p>
<p>Which Leader would you like to contact?
<select name="contact">
<option value="email1@domainname.com">Leader 1</option>
<option value="email2@domainname.com">Leader 2</option>
</select>
</p>
<p>Your Comments</p>
<p> <textarea name="YourComments" cols="50" rows="10" id="Your Comments"></textarea>
</p>
<p>
<input type="submit" name="Submit" value="Submit">
<input type="reset" name="Reset" value="Reset">
</p>
</form>
<?php
$to = $_POST['contcat'];
$subject = "Web enquiry";
$message = $_POST['YourComments'];
mail($to, $subject, $message);
?>