Answer:
The difference is that South Vietnam fell to North Vietnam and South Korea did not fall to North Korea.
Step-by-step explanation:
The Korean war ended with a armistice on 27 July 1953. technically the Korean war has not ended yet sense there has not been a signed peace agreement. The Vietnam war ended with the fall of Saigon on April 30, 1975. This is different sense The Peoples Army of Vietnam and the Vietcong successfully defeated The Republic of Vietnam or "South Vietnam". Vietnam was then unified under the communist state of the Democratic Republic of Vietnam.