How to Render Template in Application Page based on content type

Hi,

        I've created Custom Content Type for Library. I would like to create new application page to render custom content type template for new item and include custom control to attach documents after some validation. I need to save the document as well as content type fields when user click on "Save" button. Could you please help me to do it.

SPContentType ctype = root.ContentTypes["Content Type Name"];
 ctype.EditFormTemplateName = "RenderingTemplateName";
 ctype.DisplayFormTemplateName = "RenderingTemplateName";
 ctype.NewFormTemplateName = "RenderingTemplateName";

Thanks,

Varatharajan Rathinasamy.