Posting form data will work between ASP & ASP.NET. Posting data is really part of the http world, and is completely separate from ASP or ASP.NET.
As Veep pointed out, though, ASP.NET pages want very badly to post to themselves, so you need to work up something custom to make them post to different page. MetaBuilders has a nice control for just that (
ASP & ASP.NET will (technically speaking) play nicely together. However, if you continue to build ASP.NET on top of an existing clASP implementation, you will wind up with one big kludge of an application.
The only reason to EVER do this would be time constraints, and by its very nature, that puts your architecture decisions at risk of being rushed. Plus, you're building on top of an architecture that didn't even allow you to make good architecture decisions (clASP). All this is a recipe for a less-than-spectacular application.
Just a word of warning. Personally, I would never do it again. If it was a requirement of the job, then I would pass on the job.
-paul
The answer to getting answered -- faq855-2992