I would say that I like to watch Naruto, but I guess it's the fillers or just the pointless episodes that show up. So, I'll have to kinda agree with you. Although I still like watching Naruto when I'm bored and I like the action in the episodes.
I don't think the 4th hokage was Naruto's dad. Because in the beginning of the episodes they talk a lot about Naruto not having any parents. If not then I don't know because I am just starting on Shippuden.
I think it's right after the 5th hokage is picked, maybe a little after that. For the regular Naruto episodes. You will notice when there are pointless lands, battles, or if they go on pointless missions.