widgets in contacts only

there are many plugins for that, try this one, its pretty easy: http://wordpress.org/extend/plugins/widget-context/ or if you dont want to use a plugin, add a new sidebar to the specific page u desire: http://www.blogohblog.com/adding-extra-sidebar-to-your-wordpress-theme/

problem with ajax contact forms

You want to be using the AJAX API instead of trying to load files directly. Even if you got that file to load, if it uses any WordPress functions it wouldn’t work anyway. If you load a theme file directly none of the WordPress Core will boot and so none of the function will be … Read more

Contact forms not sending mails

For SMTP and Gmail, you will need turn on 2 step verification, then create an App specific password in security panel of google account. Use your email and that password as login credential. You’ll also need use TSL or SSL for SMTP. Hope this help!