I use a couple different lenses to achieve Bokeh. The lens that works the best is the Nikon Nikkor 50mm f/1.8. The 50mm lens allows me to have the greatest versatility with a great range of aperture range. Te other two lenses are the Nikon 18-200mm f/3.5-5.6 and my 80-200mm f/2.8. All these lenses achieve a great depth of field and much defined bokeh. But the best is still my inexpensive 50mm f1.8.
Another way I create bokeh is artificially in CS3. Sometime if I want to have a subject pop out of the background or my depth of field isn’t shallow for the effect I create the same effect using lens blur or Gaussian blur in layers.
The same image with an artificial lens blur layered over the image.
This is also the same image with layer mask, to allow the center of the picture to be clear.