Dragon Ball Z Episode 104: Frieza Defeated!!
Episode 104 of 291 of Dragon Ball Z, aired August 21, 1991, 25 minutes. Available with English subtitles and dub where released.
Episode summary
Frieza fires two copies of Krillin's Destructo Disk that will follow Goku until it hits him or anything else. Even so, Goku has the situation under control as the battle draws to a close and the mighty villain is going to lose.