Thanks, Michel-

>I think, if someone could help me, that it would be better to have one or a few .NET developers to recheck that entire category list and suggest more about the best set of categories for that forum.

I really appreciate the speedy reply and your suggestion about a review of topics. I like the redesigned new topic form with the ability to narrow in on a topic. I'd like the general topics to be few and general, with the ability to add on a narrower attribute. It makes a big difference if one is asking about web applications or windows applications. So, maybe:

VS.NET in general
ASP.NET
ADO.NET in General
ADO.NET SQL Server
Windows applications
Web applications
Mobile applications
.NET Framework
.NET Compact Framework
Web control library
Window control library
Class design
Deploying applications
Testing and debugging

You have a few others in the list that aren't so important to me, but I can see they might be for others so I'll let others speak up about them. For subtopics (a.k.a. version)

Grids - web forms
Grids - windows forms
Validating input
Errors

Something like that. HTH.