Yes the wheels and handles count, if they single you out to do a measurement.
If you ask me, since they invented suitcase wheels, most suitcases seem to have a lot of wasted external space where the wheels are.
Even at 24.0 inches exactly you are taking a chance with Airtran. Sometimes Airtran (haven't read any trip reports about other airlines yet) doesn't measure correctly or accurately and calls your bag oversized anyway.