Lets look at it this way, if the 4th was naruto's father, he wouldve been highly respected for the sacrifice his father made, but that isnt the case, he's though of as a monster and a trouble making brat. so the father son theory doesnt hold ground. thsi is my thoery (far fetched buit bare with me for a moment):- Im strongly leaning to the fact naruto is closely realed to the 4th, a cousin maybe. My guess is that his father hated his brother yondaim greatly as everyone always talked about how the 4th was a genious ninja and probably no one paid attention to the brother. The brother (naruto's fatehr) left the village and became an S-rank criminal. He then developed the jitsu to summon the 9 tail fox demon to destroy konoha, and as we already now the 4th sacrified his life to save the village and sealed the fox in naruto's belly. This may be the true reason why the villlagers hate naruto. let the flamming begin!