Answer
You should stand at the north geographic pole.
Work Step by Step
The tangential speed is calculated by $v_T=r\omega$
The angular speed of the earth is constant and the same for everywhere on earth, so the difference in tangential speed depends on the distance away from the axis of rotation $r$.
At the north geographic pole, the distance from the axis of rotation $r=0$, so $v_T=0$. This is the place where you have the smallest tangential speed.
