I haven't used Page Templates yet and wonder what the benefits of using them are. Can anyone help me out?

can u plz tell me how can i add new template  while adding new site to my portal, i am new to DNN but love to work on this.

my problem is i want to use my own template for my site and dont want the default templates to be shown in dropdown, for that i need some information

1. how to create a new template and how to remove old ones

2. how to upload after creating it so that it wil be shown in dropdown along with the default DotNetNuke template

 and also what the 'exported template' button does, how i can use that exported template in my new site.

 plz help me in this its really urgent.

thanks in advance

I am looking for the same info, since I am developing a portal with 5 template-like pages...

I dont want the editors to mess up the default layout of the pages.