Twenty Eleven 1.3 Theme Nav Code – HELP!

Hi Peeps,

For a few days I have been having a problem with entering this code into my header.php where am told my numberious of websites to place this but each time i place this I get a error on line 143.

I need to enter the following:

<?php wp_list_pages(‘title_li=&depth=2&sort_column=menu_order&exclude=43,45,47,49,9,37,24,20,34,17,21′); ?>

into this header.php

[code moderated per forum rules - please use the pastebin]

If you know how to do this, can you reply with the code in place please and advise me where this code has been inserted

http://misssutcliffeacademyofdance.co.uk/Home/ - I have not added the homepage content yet, thats why you can see the following NOT FOUND sign.

Thank you..