On March 26, 2003, about 1545 eastern standard time, a Cessna 150G, N3964J, was substantially damaged on the ground when it impacted a hangar and two parked airplanes at the Medina Municipal Airport (1G5), Medina, Ohio. The certified private pilot was not injured, and visual meteorological conditions prevailed for the local personal flight that was conducted under 14 CFR Part 91. According to the pilot, he preflighted the airplane, boarded, and engaged the starter. Everything seemed "normal" with the start until the engine started to "race." The airplane "lunged" forward and the pilot closed the throttle, which was open 1/4 inch for the start. He applied the brakes, but the airplane continued to roll forward towards a hangar. To avoid the hangar, he attempted to turn the airplane to the left, but the right wing contacted the corner of the building, and the airplane spun to the right impacting two parked airplanes. The pilot secured all the systems, and exited. He added that during the accident sequence, he pulled the mixture control in an attempt to secure the engine. On March 27, 2003, an engine run was performed by a mechanic under the direction of a Federal Aviation Administration inspector. According to the mechanic, he started the engine and increased power to 2,000 RPM. He then retarded the throttle to idle, and had the wheel chocks removed. Using the brakes to hold the airplane, the mechanic applied full throttle, and the airplane remained stationary. He then retarded the throttle to idle, secured the engine, and concluded the engine run. According to the Cessna operating check list, the second item in the Before Starting the Engine section stated, "Brakes - test and set." The fifth item in the Starting the Engine section stated, "Throttle - Open 1/4"."