Photography - Black & White

If you can't tell, I am obsessed with taking pictures of my children. I am constantly trying to improve my photography and my new venture is learning more about editing. I have barely even started but I was inspired by THIS post to work on my black and white pictures. I love to have black and white pictures printed and hung around our home, but all I do to edit them is hit "desaturate" in the color box. What do I get? Grey photos! Well, I decided to play around a little bit and I need some improvement, but I can already see a difference. What do you think?

Original photo. I thought I would use a picture with something black in focus.

All I did here was hit the "desaturate" button.

This is after playing with the contrast and lighting options. I included two different edits, on a little more extreme. I guess it also depends on your personal preference.