Can/how do I take black and white pics with my Nikon D50? Is Photoshop's grayscale the only way? Thanks!

Answer 1

You'll have to use an image editor, but simply converting to gray scale is a pretty brutal way to go. You can get a lot more out of your images if you take the time to tweak them.
Starting with a color image gives you a possibilities to apply filters & such BEFORE you convert to black and white, and if you have Photoshop, you can tinker with curves & levels, you can get black and white plug-ins, etc., and really improve the final result.
Here some ideas for a workflow: http://blog.photoblogs.org/2004/07/28/bw-digital-workflow/

Answer 2

Irfanview will change it to black and white also and it is free to download