Control Panel, sorting issue
No – whatever you've currently set as the sorting order (Structure, Post Date, Expiry Date, etc) in the element index in the control panel has absolutely no effect on how your entries are output in a template, or how they're ordered.

For Structure sections, the default sorting order in a template is Structure, i.e. hierarchical:

{% for entry in craft.entries.section('myStructureSection') %}
    {# Will output entries in hierarchical, chronological order #}
{% endfor %}


Keep in mind that if your Structure has multiple levels, i.e. child entries, you'll have to jump through a few hoops – using the {% nav %} tag is recommended as its able to output child entries recursively, e.g:

{% nav entry in entries %}
    &lt;li&gt;
        &lt;a href="{{ entry.url }}"&gt;{{ entry.title }}&lt;/a&gt;
        {% ifchildren %}
            &lt;ul&gt;
                {% children %}
            &lt;/ul&gt;
        {% endifchildren %}
    &lt;/li&gt;
{% endnav %}


Finally, if you want to output the entries in a non-hierarchical order, you can use the order parameter:

{% for entry in craft.entries.section('myStructureSection').order('postDate desc') %}
    {# Will output newest first #}
{% endfor %}