[SOLVED] How to have a menu button open an external web page

I am trying to understand how to have a menu button 'point' to another website.

Is it possible to have step by step instructions for a complete novice.

I would want to add a button - HOTEL, so would I have to add or change anything here -
<script type="text/javascript">myButton('HOTEL','_hotel.htm');</script>

Do I have to change anything else to point to my website - www.strandhotel.co.uk

I'm really stuck, your help would be really appreciated.