C# - Get List Of Users Belonging To A Role Using Authorization Manager

Using ASP.NET (C#) I have set up Authorization Manager to allow me to handle roles on a website. Added users to roles is simple Roles.AddUserToRole("DOMAIN\UserName", "role"). However I want to list the users belonging to a role, but since they are stored as SID's, displaying them would not be that helpful. To get the users, I am thinking XML would have to be used, although is it possible to use COM Interop to both do that and get the user name? Either way, how can I get the users belonging to a role?

The table to manage roles would basically be like this:

Role User
---- ----
admin DOMAINUserName [delete]
DOMAINUserName2 [delete]
[add user text box]
news DOMAINUserName3 [delete]
[add user text box]