For starters, it is a good idea to convert your images to black and white in Photoshop before placing them in your .indd file.
Export to PDF and print from Acrobat. Use a PDF joboptions which will reflect your printer's possibilites.
It's more of a Photoshop question, really. Here's what I tend to do:
Make a new layer from the 'Background' layer.
Add a 'Black & White' adjustment layer above that, to help optimise contrast.
Put the original and the adjustment layer in a layer group.
Make the layer group a smart object.
Convert to greyscale and save as a TIFF.
This way, the colour information stays present in a single file, and you can go back and tweak any adjustments. It's a little cumbersome and makes for fairly large files, but you can automate it.