Best mechanism to have rich form controls on web page (HTML) equivalent to windows forms

Question

I am working towards porting a windows application to web. The windows application is quite rich w.r.t. the form controls, complex validations and user interactivity.

Basic web forms are inadequate to meet these complexities. So I would like to know the best way to still have the richness on the web pages. I have some ideas and would like comments.

1. Use DHTML & Java Script to mimic complex controls. There are some macro controls available as part of jQueryUI that can be used and some other third party Java Script controls. I'd like suggestions if there is a recommended control library.
2. Use RIA (preferably Silverlight) wherever rich controls are needed. I'd like to keep this as a last option because it mandates the Silverlight plug-in.

What are other popular / preferred strategies?

Answer 1

If you don't mind a departure from .NET "controls", I'd try Ext JS. It is dual licensed GPL/Commercial so you'll likely have to pay for it, but the components are more robust than Telerik or the other .NET versions.