This, for me, is one of the Greatest ever Formula 1 first laps. Williams did 1-2 (Prost and Hill) in Qualifying. At the start, Schumacher blocks Senna, sending him to 5th position. Within one lap, Senna was leading the race. Only he could do that under that rain.
You can Skip the video up to 2:54 to avoid the warm-up lap.
Agustin.