.NET Framework 2.0 vs 3.5/4.0... any possible advantage to use the older version?

Question

My project leader insists on using Visual Studio 2005 which only targets the .NET 2.0 framework and only supports C# 2.0 syntax.

He insists that the 2.0 framework has higher compatiblity and performance for older computers. By old, I mean 5-8 year old Windows XP machines.

Assuming we only support a minimum of Windows XP / Server 2003, is there any advantage at all to using .NET 2.0?

I am pretty sure that even targeting .NET 2.0 we can take advantage of C# 3.0 syntax in our code (lambdas, auto-implemented properties, etc.) if we upgrade past VS2005.

Answer 1

.Net 2.0 is considered to be more widely deployed, but 3.5 isn't far behind any more. However, that's no reason to limit yourself to Visual Studio 2005 or C# 2.0. Visual Studio 2010 can target .Net 2.0, and use C# 3.0 features when it does so to boot.

Answer 2

.NET 2 is no longer supported by Microsoft. Well, Microsoft makes the terms tougher to explain. For Windows XP and Windows Server 2003, you have to at least use .NET Framework 3.5 SP1,

http://blogs.technet.com/b/lifecycle/archive/2010/04/30/net-framework-3-5-sp1-and-later-now-supported-as-part-of-microsoft-windows.aspx

so that you can receive assistance from Microsoft support team.

Therefore, I see no reason to stay on .NET 2.

"the 2.0 framework has higher compatiblity and performance for older computers" is a joke for me. When you lose support-ability from Microsoft, you lose everything.