When you open a new C# Windows Forms Application project in Visual Studio 2008, you get a lot of autogenerated code (AssemblyInfo.cs, Resources.Designer.cs, Settings.Designe
Most of those files are templated and you can modify their inclusion in a new project and what is contained in the files. You can even create your own templates for new project types or items. http://msdn.microsoft.com/en-us/magazine/cc188697.aspx
As far as modifying what is already there, unless you're sure that every project you're going to work on is going to need those changes I wouldn't recommend doing that, it's easier to just create a new template for a different project/file type.