Based on https://craftcms.com/docs/lightswitch-fields and http://craftcms.stackexchange.com/a/352/5134:

{% if entry.lightswitchFieldHandle %}
    {% if currentUser %}
        Display entry that only logged users can see
    {% endif %}
{% else %}
    Display entry that anyone can see
{% endif %}

Based on https://craftcms.com/docs/lightswitch-fields and https://craftcms.stackexchange.com/a/352/5134:

{% if entry.lightswitchFieldHandle %}
    {% if currentUser %}
        Display entry that only logged users can see
    {% endif %}
{% else %}
    Display entry that anyone can see
{% endif %}