Alright, well in that case I'll feel free to spoil the game for you.
A lot of people (including Yahtzee) are critical of the game's ending, because Joel decides to be selfish, and rather than allow Ellie to be killed and studied for a cure (which is what she wants), he kidnaps her, kills the doctors operating on her, and then lies to her about the whole thing, all so that he doesn't have to lose her the way he did his daughter. Now, considering that this is a completely story driven game, a very large part of whether you like the game hinges on the story, and especially on the ending.
From the perspective of a parent, as they play the game and Joel becomes more and more of a father figure to Ellie, the player begins to think of Joel's choices in the game regarding Ellie in the light of "well how would I react if that was MY child." Because of that perspective they are a lot more likely to accept the ending and see Joel in a good light, rather than as a selfish asshole who doomed the world, because they know that if put in the same situation, where they had the choice of sacrificing their kid in order to save the world they would say "screw the world." So the ending ends up having more impact to parents who end up internalizing the conflict and sympathizing with Joel.
Do you need to be a parent to enjoy the ending? Hell no. Like I said, I'm not a parent and I dislike children, but I found the ending to be very human, which colored my perception of the rest of the game's design choices and mechanics retroactively, once I knew how the game had been planned out by Naughty Dog all along. Casual Shinji talks about the mechanics of the game better than I do, so you should read his post, but he essentially says everything that I want to about it. Essentially it's a kind of "sum of the parts is better than the whole" thing, where all the mechanics are perfectly held up by the story being told. If you don't like the story then you won't be forgiving of the mechanics, because the mechanics are clearly emergent from the needs of the story.
So I do think it's valid to think that parents are less likely to find fault with the game because they'll be heavily engaged with the story. Are they going to be significantly more engaged than everyone else? Not necessarily. Are people who aren't parents going to necessarily be more critical than parents? Also not necessarily.
As far as the xbox fanboy comment goes, I'm pretty sure that was supposed to be a joke. An asinine joke, but a joke nonetheless, so no need to get too ruffled up about it.