All of them of course..
I would recommend the Framework and the Database Deployment toolkit at a minimum. The DDT is a huge bonus if you use SQL but can be useful if you don't. If you need any type of Security for your application then the Role-Based security application is a very popular module and can add much strength to an application.
The Enterprise Server is an amazing addition to the StrataFrame family. It is a datalayer that implements a smart-client application. You can design your application today and simply change its datasource (6 lines of code) later and be operating in a web-server environment. The developer SDK for ES is free so it is not necessary to make any decisions initially.
If you need any further information our sales department will be more than happy to help. sales@strataframe.net
Thanks,
Steve