Add items to a select box in _form.rhtml

<p><label for="account_type">Type</label><br/>
<%= select 'account', 'account_type', 'user' %></p>
<!--[eoform:account]-->

How can I add other elements i.e. guest, adminstrator to the list in the
selection box.

<%= select 'account', 'account_type', [['user','user],
['guest','guest],['administrator','administrator]] %></p>

should work. But if you had an AccountTypes model the API docs show
you a much more elegant way to achieve it:
http://api.rubyonrails.org/classes/ActionView/Helpers/FormOptionsHelper.html#M000506