Is Crystal Reports the tool to use? If not, what can you recommend?

It depends on the # of users.

If you're using the version of Crystal that comes with VS2005 (basically, the developer edition), Crystal on the server will allow up to three users to run a report (any report) at the same time. So if three users are executing a report at the same time, and let's say the execution takes 15 seconds....any other users who try to run a report will be blocked out.

You can obviously put your own try....catch block in, to detect such a situation - but depending on the # of users who will be running reports simultaneously, that might be an issue.

Some people try to "get around" this issue by having a single CR.NET application sitting on the server. When a user wants to run a report, their selections/options are written to a custom database file, and the server app "polls" this database file for report requests, and then generates a PDF for the web user to ultimately view.

So bottom line, think about all your usability requirements and deployment issues.

In general, CR is the best general-purpose report writer today, it has more functionality than Reporting Services....but you'll need to think about these multi-user issues.

Hope that helps...
Kevin