Setting up form table checkboxes
Drupal has a built-in tableselect element type for situations just like this, it would be a lot easier to use that instead:

$disputes = array(
  1 =&gt; array('Joe', 'Smith'),
  2 =&gt; array('Susan', 'Doe'),
  3 =&gt; array('John', 'Doe')
);

$header = array(t('First Name'), t('Last Name'));

$form['checkboxes'] = array(
  '#type' =&gt; 'tableselect',
  '#header' =&gt; $header,
  '#options' =&gt; $disputes,
  '#empty' =&gt; 'No users were found.'
);


The above code produces this table:



In your form submit function you can get the selected user ids with code like this:

$selected_uids = array_filter($form_state['values']['checkboxes']);


EDIT

The above is for Drupal 7, if you're using Drupal 6 you can use the same code but you need to install the Elements module.