Email scheduling in ASP.NET

I am developing email marketing application with ASP.NET 2.0 and SQL Server 2005, it has a facility to schedule email. I have to develop a scheduler.

I might face attaching the user files in the mail. Assist me through steps.

Can I able to schedule email in ASP.NET or I should use SQL Server. If so how and also tell me how to attach files which is in physical path like c:/file.jpg?

 
...