Hi, Ivan,
You've gotten great information from Einar and Eric and others, so I don't want to repeat much....other than to say that I've been using Crystal and the stored procedure model for years, and I find it's the best way to go.
While Crystal can be touchy sometimes, it remains the best general purpose report writer around, with the best overall feature set.
Also, I have a book coming out on Crystal .NET development late next month:
http://www.apress.com/book/bookDisplay.html?bID=10147Kevin