When I wanted to make a picture black and white in Photoshop, I would open the image then click on Image-mode-grayscale. It made the picture black and white, but also a little flat, drab and dull. I have discovered three better ways to make it black and white and here is the easiest of the three. I think it beats the grayscale mode hands down.
First open the image in Photoshop. Go under the image menu, under mode, and choose Lab color. This changes your picture from RGB (red, green blue) to Lab color. You won't notice a difference in your picture in the layers mode, the difference is in the channels. Now instead of having a Red, Green, and Blue channel, the luminosity (detail) of the photo has been seperated from the color which now resides in two channels named "a" and "b". The lightness channel contains the luminosity of the photo.
Click on the channels panel (found under the window menu) and click on the lightness channel. Now go under the Image menu, under Mode, and choose Grayscale. Click okay on the resulting warning dialog box. Take a look at your photo now and see if it looks to light or too dark. If it's too light, go to the layers panel, click on the Background layer and then press Ctrl-J to duplicate the background layer. To make this layer darker, change the layer blend mode to Multiply (right under the word layers in the panel you will see a drop down box that right now has the word "normal" in it. Click on the triangle and then click on the word multiply). Now lower the opacity of this layer until your image looks just right.
If your photo was too dark then change the blend mode to screen instead of multiply and dial in the opacity.
Here are the results:
Grayscale
The Lightness Channel Method with some text for the finished picture: