According to the pilot, while on final approach to land on a 2,502-foot-long, asphalt runway, he observed another airplane back-taxiing on the runway and then depart. He continued the approach, performed a "normal" full flaps landing, and the airplane touched down about midfield. During the rollout, he determined that there was insufficient runway remaining to stop, and chose to attempt a go-around. The airplane subsequently struck the airport perimeter fence and then a roadway guard rail before it impacted terrain, which resulted in substantial damage to the wings and fuselage. The pilot further reported he did not experience any pre-accident malfunctions or failures that would have precluded normal operation. He also stated that the accident might have been prevented by aborting the landing earlier.