List Menu

Sure. For this simple example you would use the select method.
Instead of <%= text_field 'registration', 'gender' %>, you'd use:

<%= select 'registration', 'gender', {"Male" => "Male", "Female" =>
"Female"}, { :include_blank => true } %>

Check the <a href="http://api.rubyonrails.org/classes/ActionView/
Helpers/FormOptionsHelper.html#M000506">documentation</a> for more
details.

Marc