It is so easy to use the aspnet built-in SQL Providers...

Create the aspnet database (aspnet_regsql at a command prompt)
Insert the SQL Connection in your Blog Web.Config,
Set the SQL defaultProviders,
Create Roles "Administrators" & "Editors", a default Admin account and you're done...
http://blogengine.codeplex.com/wikipage?title=MSSQLMembershipRoleProvider - Watch the videos

Create the first users & roles?
Use the built-in Membership Administration Website (VS.NET: Website, ASP.NET Configuration)