Important folders and files by default in Windows

You could quickly get to those by Start - Run - paste folder

:: where are the assemblies
%ProgramFiles%\Reference Assemblies\Microsoft\Framework\v3.5
:: where is the machine config file ?
%windir%\Microsoft.NET\Framework\\config\machine.config
::where is the csc.exe
dir %windir%\Microsoft.NET\Framework\*csc.exe /s /b
%windir%\Microsoft.NET\Framework\v2.0.50727\csc.exe
%windir%\Windows\Microsoft.NET\Framework\v3.5\csc.exe

Windows Vista
%AppData%\Microsoft\Windows\Recent
Windows Vista's code snippets location for Visual Studio 2008
C:\Users\%userName%\Documents\Visual Studio 2008\Code Snippets\Visual C#\My Code Snippets