Gulmira > Stark Expo > Malibu mansion > Monaco Grand Prix > Air Force One > Miami shipyard > Iron Man vs Iron Monger > Mark I cave escape
None of the other scenes are truly Iron Man action. Honestly the best balance of action overall was probably seen in IM3, it was nearly non-stop. But that does not make a movie great.
EDIT: I was just thinking how global the Iron Man series has been.
IM1: California, Afghanistan
IM2: New York, Monaco
Avengers: Germany, New York
IM3: California, Miami, Tennessee