I am with Jim.    I do dynamic before with a slow easy 1-2 miles, before I pick it up!  I do static after for most of my runs.

If I do dynamic stretching/warmups (I don't always) I tend to focus on the hips.  I'll stand on one leg and swing my leg as far to one said and then as far to the other as I can.  I'll swing it back and forth for a while - just to get things woken up.  I'll then do the same thing front to back.  Then the other leg.

Static stretches are the mega-classic stretches we've all done.  Lean up against a wall and put one leg back straight to stretch the calf, etc.  Putting your straight leg up on something to stretch your hamstring is another.  Any stretch where you hold the limb still for 30+ seconds would be considered a static stretch. 

I wanted to add my personal experience in case it helps.

I had run for many years two-three times a week (4-5 miles every time) and I always did static stretches before and after the run.

About one year ago, I started running longer and more often and started experiencing some muscular problems (mostly to be attributed to the increase in training load).  Then I read about dynamic stretching and switched to dynamic stretches before the run and dynamic stretches afterwards. I even did some experimenting on the subject and my general feeling is that my legs always feel a little heavy at the begining of the run, but this goes away faster when I do dynamic stretches instead of static. Post run recovery time looked a little easier this way too.

I am also posting you a link on dynamic stretching that helped me: http://www.runnersworld.com/article/0,7120,s6-241-287--13442-0,00.html. I ended up with a combination of the exercices described, I focus a lot on warming my ankles up (tip of the foot on the flor and circular movement both clockwise and counterclockwise) and then do walking lounges and leg lifts. I have to say that I used to get some funny looks by other fellow runners at the begining (dynamic stretching is more noticeable than static), but since then the number of "dynamic stretchers" in my neighborhood has increased significantly.