ReferenceError SubmitForm not defined

ReferenceError SubmitForm not defined

I have 2 errors, 
1.  is the onload the page doesn't load the AJAX JSON response data.  The data returns but doesn't get displayed so the error is JQuery somewhere.

2.  When you click in the form fields you get the error "ReferenceError SubmitForm is not defined".  This may be why the page doesn't load.   So I'm guessing the problem is with the form inputs (red) or with the submitForm function.  

My page:
janisrough.dyndns.biz/todo16.html

 <div id="todos">
    <header>
        <h1>Taskos</h1> 
        <h2>&mdash; a tasklist todo app &mdash;</h2> 

   
        <form id="taskForm" onclick="return submitForm()">   
            <input  name="task_todo" type="text" value="What needs to be done?" /><br />
            <input  name="todo_name" type="text" value="By whom?" />
            <input name="due_date" type="text" value="By when?"  /><br />
            <button type="submit"  class="fg-button ui-state-default">Submit</button>
        </form>

</header>


    <section class="main">
    <form id="task-list"> 
        <input id="toggle-all" type="checkbox" />
        <label for="toggle-all">Mark all as complete</label>
      <ul id="todo-list">
      </ul>
      </form>
    </section>
              
     <footer>
      <a id="clear-completed">Clear completed</a>
      <div id="todo-count"></div>
    </footer>
</div>

----
function submitForm() {
 $.ajax({ type: 'POST',  
         url:  'ajax/form_handler.php', 
       dataType : 'json',
         data: $('#taskForm').serialize(),
        success: function(response) {

console.log(response);
$("ul").append(response);
     
                        }
});//success end ajax end  

   return false;

};//end submitForm 

Thanks,