Both are correct, but I'd replace when with 'while' in the second sentence.

Both are correct. Neither is better. "While" might be better than "when" because crying continues over a period of time, but that is optional. Additional choices are: I cried while watching this scene. I cried as (or "when") I watched this scene. I was crying when I watched this scene.

Correct your spelling: cried. Yes, both sentences are correct. However, there is a slight difference in meaning between the two. The sentence "I cried watching this scene" is in the simple past tense. This means that the action of crying happened at a specific point in the past. The sentence does not specify how long the crying lasted or whether it was continuous or not. The sentence "I cried when I was watching this scene" is in the past progressive tense. This means that the action of crying was happening over a period of time in the past. The sentence implies that the crying lasted for a while and that it was continuous. In general, the past progressive tense is used to describe actions that were happening over a period of time in the past. The simple past tense is used to describe actions that happened at a specific point in the past. So, which sentence is better? It depends on what you want to say. If you want to emphasize that the crying lasted for a while and that it was continuous, then the past progressive tense is the better choice. If you just want to say that you cried while watching the scene, then the simple past tense is fine. Here are some examples of how the two sentences could be used: "I cried watching this scene. It was so sad." "I cried when I was watching this scene. I couldn't stop." In the first example, the simple past tense is used because the speaker is simply stating that they cried while watching the scene. The sentence does not specify how long the crying lasted or whether it was continuous. In the second example, the past progressive tense is used because the speaker is emphasizing that the crying lasted for a while and that it was continuous. The sentence implies that the crying was so intense that the speaker could not stop. The best way to choose between the two sentences is to consider the context in which you are using them.