[Plugin: Theme My Login] Need help using it

First of all thanks Jeff for creating such a plugin.

I need some help using it. Below is my web page
If you check on the right hand side, u will see the LOGIN widget. The issue here is the username and password field is too big. How shud i reduce it?

When I click on LOG IN at the top of the page, the plugin is not used there. The register page shows the same as log in page.
http://www.gangzonline.com/login/?action=register

I read this
**Page ID
This should be the ID of the WordPress page that includes the [theme-my-login] shortcode. By default, this page is titled “Login”**

I don’t know how to use short code. Can you please help me using it? Any help wud be highly appreciated.

Thanks