English is a tricky bastard.
And either sentence is possible (i.e., grammatical), given the right circumstances.
Say the speaker (let's call him Sal) is narrating an event that takes place entirely in the past, that is, he's telling a story or relating an event in the present from the point of view that it is over and done with; in this case you get the more probable result that (2) is correct, precisely because it is past narration, or narration about the past.
On the other hand, for (1) to be correctly used, consider Sal to be a story-teller, but this time he is telling a story about the present, and in doing so he uses the historical present, also called the story-telling present. Then, Sal can spin off some thing like
Three years ago, Bob wanted to know if he is a father or not. Today, Bob wants to know if he is an uncle or not.
Here, Sal switches midway through his first sentence from past narration to historical present. His use of if he is a father or not alerts the listener to this switch and prepares said listener for the present tense in his second sentence. The parallel use of present tense is in both sentences is important to Sal's story and it wouldn't carry the same force without it.
Which, once again, asking for analysis of individual sentences devoid of functional and/or communicative context as well as perceived speaker's intention is chock full of problems and hardly allows for how language is used.