Visual C++ General
There are two ways of doing this:
1) Use the property sheets feature (vsprops) to create settings that you can then inherit from.
http://msdn2.microsoft.com/en-US/library/a4xbdz1e(VS.80).aspx
2) Use multiple selection in the solution explorer and select the projects you wish to change. The changes you make will be applied to all projects and files currently selected.