Really, you shouldn't treat guesses as facts; people may believe it.
Black Beard as Ace and Luffy's father is just plain nonsense. Do you really think Ace would hunt his own father, trying to kill him? And that his father would be someone "weaker" than him? If Luffy and Ace's father was a pirate, he would be a great one.
Also, that's not for sure. We don't know if Gol D. Roger is Luffy and Ace's grandfather, so don't treat it as a fact. And I think it would suck if he was their grandfather. It's just too "obvious".
Monkey D. Luffy, Portgas D. Ace, Gol D. Roger, and Marshall D. Teach. It's obvious they are somewhat related, linked within the "D." name. However, we still don't know the relationship among them all.
Also, please stop treating this "Aqua" nonsense as a fact, too. There's no character named "Aqua", for those who are still confused