First turn your image into grayscale.
Then choose one of the Duo-tone/ quad-tone / pantone options. (all under image > mode > grayscale + duotone.)
Look under the help (for above subject) the get a better idea of each steps.
===
BW and other duo-tone types don't usually print well in glossy inject printers. You might have to use matte paper. No big deal if the picture will be under plastic sleeve, glass, etc. As glossy and matte looks identical under them.
Good luck...
