One way to keep site visitors from clicking a checkbox you don't want them to check is to delete it. You can write code that deletes a checkbox every time your page loads or in response to a user's ...
Since Bootstrap's col-xs-* classes are applicable to all form elements, you can use them on your checkboxes too! This way, the checkboxes will be evenly spread out ...
{html_checkboxes} is a custom function that creates an html checkbox group with provided data. It takes care of which item(s) are selected by default as well.