Help needed on Reporting Services provided by SQL

Question

Hi, I Need to know how to use Reporting Services of SQL Server to customize the reports to be developed in .NET interface Example : The reports have to b VERY dynamic and customizable..i.e. The user can choose what fields go on the reports, what to group on, what to sort on, etc... Can we achieve this by programatically editing the .rdl file? If yes, then how to publish the report?