Adding new routes dynamically

Hi,

I am developing a site where i am usgin ASP.net Routing insted of ASP.net Re-Writing.

I have added routes like below for all my pages.

ex for home page RouteTable.Routes.MapPageRoute("HomePage", "Home", "~/Home.aspx");
for about us RouteTable.Routes.MapPageRoute("AboutUs", "AboutUs", "~/Aboutus.aspx");

1) Is this a correct way to use routing to simplyfy URLs??
2) How I can add new routes for the pages created dynamically??
For eg : I have given a option to admin to add new pages (physically) from backend and now he should able to give a SEO friendly URL. How to do this??

Kind Regards,
Jay