API - Get System Information

1. Operation System Version:
   GetVersionEx: http://msdn.microsoft.com/en-us/library/ms724451(VS.85).aspx
2. Hardware, such as processor, memory:
   GetSystemInfo: http://msdn.microsoft.com/en-us/library/ms724381(VS.85).aspx
3. SystemDirectory, WindowsDirectory:
   GetSystemDirectory: http://msdn.microsoft.com/en-us/library/ms724373(VS.85).aspx
   GetWindowsDirectory: http://msdn.microsoft.com/en-us/library/ms724454(VS.85).aspx
4. User name and computer name:
   GetUserName: http://msdn.microsoft.com/en-us/library/ms724432(VS.85).aspx
   GetComputerName: http://msdn.microsoft.com/en-us/library/ms724295(VS.85).aspx
   GetComputerNameEx: http://msdn.microsoft.com/en-us/library/ms724301(VS.85).aspx
5. UI and Display:
   GetSysColor: http://msdn.microsoft.com/en-us/library/ms724371(VS.85).aspx