Create some of the pages BW and others Color in the same document as pdf.

To be more specific, we know of no applications themselves or generic PDF creators that have settings on a page-by-page basis that force conversion of color to grayscale during the PDF creation process itself. This includes all Adobe applications and features provided by Acrobat.

The simplest way to get this effect would be to create a PDF file of the first page in color and then create a separate PDF from the remaining pages using settings to force grayscale for that file. (Such an arrangement is easily done in Adobe InDesign, for example, but not in other applications including printing to the Adobe PDF PostScript printer driver instance in Windows.) Then, combine the two files in Acrobat and save the result.

Alternatively, you could create two full color files and then after file creation, use Acrobat Preflight to the second file to grayscale and then combine as above.

          - Dov