You would have to have the highest floor possible with a North/North east facing window, although best you will probably see from the hotel's location is the final approach to 27R. Most of the view of the airfield is blocked out by T4. The best hotel for views of the airport is the Renaissance. It has fantastic views of 27L/09R and Terminal 1 and the top end of T3. They even have have special spotter rooms/rates that are availiable on w/ends.
Hope this helps.
"She Rolls, 45 knots, 90, 135, nose comes up to 20 degrees, she's airborne - She flies, Concorde Flies"