When Igor (the big armor) is shown for the first time in the movie, the suit heads over to one of the crane's legs and stays under it to keep it from falling down but the crane doesn't fall down after all the suits have self destructed.
According to Tony, the suits are coded only to him (with the exception of War Machine/Iron Patriot), however Pepper is able to operate the last prototype when it first comes on to her. Though this could be explained by a malfunction in the suit, near the end of the movie she is able to fire one of the arm/wrist components from another Iron Man suit.
When Tony Stark first discovers the explosion in Rose Hill, TN, the map he views shows the town in extreme northwest Tennessee. However, later in the movie, the Miss Chattanooga pageant is taking place in what we assume to be Rose Hill. Chattanooga, TN, is in extreme southeast Tennessee, the complete opposite corner of the state.
When in the News van, Tony tells the operator to get on the roof and re-arrange the ISDNs. ISDN lines are land lines, not really used for the past ten years. Dishes would use either Satlinks or Cellular networks.
When Happy is in the ICU the nurse adjusts the roller clamp to the IV fluid. A pump controls the flow-adjusting the roller clamp would do nothing except shut off the medication, causing the machine to call for attention.