If somebody asked me to pass them some apples, and wasn't sure which apples they were referring to, I might point to the apples I think they mean and say 'These apples?' The implication is '[Do you mean] these apples?' Perhaps i'm just trying to shoehorn my lazy English habits where they're not welcome ;-)
In this scenario, I guess you would need the accusative because the apples are the object. A better example could be if someone said: "The apples taste good." - "These apples?" = Ezek az almák?" However, as I understand it, you always need the definite article "a/az" in between forms of "ez" and the noun if they belong together as a subject, since "ez" implies that you are talking about something specific. When there is no article it means you have a subject and a predicate. Am I right?
I'm still trying to understand questioning intonation. It sounds like the last syllable is stressed here rather than the second last. Someone previously said that that generally only happens in very short sentences (the example was with a single word of only two syllables) but two words and four syllables is not extremely short.
I think what happens here is that since the emphasis is on the word "almák", that has to be the stressed word. But since it only has two syllables, the stress is on the second one. If you would ask: "Ezek az almák?" meaning "these apples?" where the emphasis is on "ezek", the first syllable of the word would become stressed. Another example: "Ezekben a nagy piros házakban élnek? which could mean either: "Does anyone live in these big red houses?" or "Do they live in these big red houses?", it's the same case. Even though it is a long sentence, the stress would be on the very last syllable in the first sentence and the second last in the second.