The simplest form of copyright is simply to place the following notice
in the code and in the documentation: This banner should also appear at
the opening screen of the program in operation and/or in the "About"
menu option of Windows(tm) platform programs.

   <Program title>, Copyright <Year> <Your Name>.
   All rights reserved.

The "All rights reserved" statement means the author retains all rights
to the software, it's use and disposition, that are not expressly
covered in the documentation. The rights of the public should be given
as a "limited license" in the documentation and usually cover the use
and permission to copy the full and complete archive for further public
distribution.

Some sites dedicated to legal aspects of shareware, are listed at the
end of the FAQ.