I tried this evening very funny about hiding SharePoint List Fields in NewForm and EditForm pages of the List.
The result is ver simple when i used JQuery, just in a few lines for getting the result of what i need.

Show Fields

Fig-1 Show Fields

Hide Fields

Fig-2 Hide Fields

In my list i have Five Fields , on that we have CheckBox Yes or no type field use to show or hide the other fields.

The Checkbox title is ShowFields, if that checkbox is selected, the three fields will be Visible on the page,
if that Checkbox is uncheked those fields are gone to be hidden.

I used Content Editor webpart for adding JQuery script, if u want to add CEWP to NewForm and EditForm pages, just type  &ToolPaneView=2 on the end of the url
(eg., http://server/Lists/SampleList/NewForm.aspx?RootFolder=%2FLists%2FSampleList&Source=http%3A%2F%2Fserver%2FLists%2FSapleList%2FAllItems%2Easpx&ToolPaneView=2 )

Or wen ca also use the SharePoint Desinger as a editor to the Page

Add the following jquery code in ContentEditor WebPart

<script type=”text/javascript” src=”http://ajax.googleapis.com/ajax/libs/jquery/1.3/jquery.min.js”></script>

$(“input[title$=’First Name’]”).parent(‘span’).parent(‘td’).parent(‘tr’).toggle();



In the above code the inputfield with the title ShowFields is Clicked, that click event fires the fields to be hide or show.