no that is not the one , there are many useful adapter for a multitude of slr and rangefinder lenses , some are excellent some are just good and some are best avoided
i have many rj adapters, that is one pretty good brand and cheap....,i have adapters branded "RJ "
for contax g mount, contax slr, nikon slr, rollei slr , and konica slr and all work well and you should be able to get the nikon one for less than 40 dollars US funds,.............. novotron on the other hand is very expensive but finely made
it pays to do a little homework ......the info is out there on the internet. and on the forums , so you dont end up with a lemon
The Panasonic adapter mentioned will adapt regular FourThirds lenses to micro-FourThirds mount of your E-P2. In other words you can use the wide range or Olympus and Panasonic 4/3 lenses on your E-P2 and you will get to control your aperture and even have full AutoFocus with some of the FourThirds lenses.
The only way to use that adapter for your Nikon lens is if you stack yet another adapter on top of the panasonic, you will need a /Nikon-To-FourThirds/ adapter.
Note that is perfectly possible to stack multiple adapters but i recommend it only if the total weight is manageable by each individual adapter.
See for example this picture below where i have two adapters between E-PL1 and Zuiko OM 50mm lens.