What if Harry knew he was a wizard before he turned 11?
well thats just to bad for the dursley's
What if Harry was born an animagus and he knew it?
i donno that would be pretty freaky
What if Harry hadn't been able to speak parsel-tongue?
than that dude would have died and harry wouldn't of had to worrie about hearing the voices in the second book
What if Lupin had bitten Harry?
than harry would be just like lupin had been in his school days and dumbeldore probably would have suggested what he did to sirus and james
What if Hermione didn't get the time-turner?
buckbeak would more than likely be dead and sirus well he would have died earlyer OR dumbeldore would have figured some other way to save them