WIN32_EXTRA_LEAN does not do anything. Please refer to Windows.h for information concerning the NOxxx symbols that are being defined.
Newly-generated Visual C++ 5.0 and later AppWizard applications automatically benefit from VC_EXTRALEAN. You can also manually define VC_EXTRALEAN to speed the build process of many older MFC applications.
WIN32_LEAN_AND_MEAN: Windows Headers use this symbol to exclude rarely-used header files. Please refer to Windows.H to determine the files that will be excluded when this symbol is defined. Since MFC defines WIN32_LEAN_AND_MEAN, all MFC projects automatically use it.
Non-MFC C++ and C applications can define WIN32_LEAN_AND_MEAN and any applicable NOservice defines, such as NOSOUND (see DevStudio\Vc\include\Windows.h), to reduce their build times.
To add these defines, from the Project menu, choose Settings. The Projects settings dialog box appears. Click the C/C++ tab. In the Category list, select Preprocessor. Add the desired definitions to the Preprocessor Definitions box.