From what you have said, Yes it is possible, as you stated. You provide the choices from which the user can pick from, and from the selections (essential just variables given the value by the selections made by the user) you should be able to pass those in to create reports.

Not saying I know how to do it off the top of my head, but essentially the logic is the same as the report generation in an Access Project. Same exact principles of a set of choices providing the sources of data on which to create the report.

Hope this makes sense. If you want actual code, that is something I would recommend you attempt and ask of assistance as needed.

i would like know how to create dynamic reports in asp.net.
can anyone give me code

It is more than just code. Reports are the output of your data stores, so design is as much of a consideration as code. It is not like I can say here, this is the code for writing a Crystal Report in ASP.Net, it is a little more involved than that. S

So saying that here are some questions I have:
Q Do you have Visual Studio 2003 Architect or better? <-- At least do you have Visual Studio 2003 with Crystal Reports Installed ???

That is your number one requirement!!

Second, give this link a read : LINK

Now I am willing to help you on any questions you have, but you have to put some effort and supply the code/design materials you are having issues with, for me to be able to help you.