Conversations

Jake: Which of the following sentences are correct?
Dan: Sentence 1 would be correct if it weren’t missing a comma. The sentence 2 is correct.

Jake: Which of the following sentences are correct?
Dan: The sentence 2 would be correct.

Are these two short conversations correct? In the first conversation ‘would’ is conditional. In the second conversation, ‘would’ is not conditional but rather used to show politeness. Am I correct? Please explain why the use of would are different in the conversations above. Thank you.