Use Photo Posts to showcase pictures. They are similar to regular WordPress Posts, but they can be controlled (displayed or excluded) in the loops, in the RSS feeds and in Cleio Maps.
Customizing the Photo Posts template
You could also customize the template individually.
To do so, make a copy of your single.php template and rename it into single-photo.php.
Latest Photo Posts Widget
This widget will showcase your latest Photo Post.
You can customize the title (e.g. Photo of the week, Photo of the moment, etc.) and choose wether to display the Photo Post title or not.