Create form for image selection from the content
Like most things in Drupal there are a couple of different ways you could do this. A quick look into the challenge, reveals the Webform View module. Basically, it allows you to pull in a viw (list of your nodes) as selectable items, for a webform. Webforms are good if all you want to do is store (and email of course) the submitted values of a form for manually processing later. Webforms are typically used for feedback, survey, contact forms.

If you need to do something a little more flexible with the submitted values, alternatively you could use the Views Bulk Operations (VBO) module (add-on for Views) which provides this kind of functionality plus a lot more if you need it for other purposes too.

Basically, you would create a view listing your content items with the fields you want to display, and then add a "Bulk operations: Content" field, and select the "Pass ids as arguments to a page", and then specify the path you want the arguments sent to. The path could then be defined in your custom drupal module, and you could use the $arguments = func_get_args(); to get all the arguments sent through. e.g. in a sandbox_test.module

function sandbox_test_menu() {
  $items = array();

  $items['test-submit'] = array(
    'title' =&gt; 'VBO Test Submission handler',
    'page callback' =&gt; 'sandbox_test_vbo_test',
    'access callback' =&gt; TRUE,
  );

  return $items;
}

function sandbox_test_vbo_test() {
  $output = '';

  $args = func_get_args();
  if (is_string($args[0])) {
    $items = explode(",", $args[0]);
    $output .= '&lt;pre&gt;' . print_r($items, true) . '&lt;/pre&gt;';
  }
  else {
    $output .= 'None found';
  }

  return $output;
}