Welcome to Nikonians! Congratulations on your new D5000! As George said, DOF is a function of the Aperture, focal length, and camera to subject distance. A DSLR will allow you to control the DOF. The smaller the Aperture (larger the f/# eg. f/16) the greater the DOF. The larger the Aperture (smaller the f/# eg. f/2.8) the narrower the DOF. Good Luck and Enjoy your Nikons!