This is a very dangerous topic. Everyone will likely tell you that the language they work with on a regular basis is the best one to use. Same with Mac vs PC or Oracle vs SQL Server.
To choose a language you should do an analysis of your needs (requirements of your applications) and your skill set (very important). And match them to the languages features. Just having a certain skill set available could be enough of a reason to go with any of the major languages.
Here are some questions to be asked:
Is this a commercial web application to be hosted in a space.
Ability to spend on software licenses
Ability to maintain.
The decision of programming language should consider the clients ability to spend on infrastructure.
ASP.NET/C# is one of the best recommendation people would give. C# is the future language and programmers love it. It accelerates the development cycle, and the recommended language for the Web. There are plenty of examples.
The easiest tool for web apps with MS SQL is ASP.NET with C# or VB.NET. But the catch is whether the client is ready to invest in a server license and maintenance. The other option is to go for JSP, which is open source and does not require server licenses, but application development would be slow, as would maintenance. Also look at ColdFusion.
If you are comfortable with JavaScript syntax, it won’t be difficult to pickup C#. If you are comfortable with VBScript, then it won’t be difficult to pickup VB.Net. There is a higher demand for C# developers than VB.NET in the job market.
If you’re an experienced developer or a manager, it helps to consider these, when choosing a platform:
Longetivity. How long is the technology valid?
Development cycle time.
Deployment time.
Compatibility issues with other OS.
a minimum of these. If you go by that, asp.net/C# is the future.