4) Naruto -
I was an elitist anime watcher, and because of this I was pretty harsh against people who watched Naruto, Bleach, DBZ, Inuyasha, and all of those other Cartoon Network anime. After I was running out of series to watch, I decided to give Naruto a fair shot.
I don't see how anyone can watch several episodes of this series, and really have negative opinions towards this series. Naruto has been able to pull every emotion out of me. I have been filled with complete joy, sat in deep suspense, laughed, and even gotten teary eyed. The characters are amazing, and the plot is even better.
The only thing that I think is bad about the series is the 85 filler episodes from episode 136-220. The first thirty or so were pretty good, but after that they started becoming complete trash. I actually skipped episodes 180-219, and went on to Naruto: Shippuden. These filler episodes were necessary so that the anime did not catch up to the manga; however, a new watcher can easily skip the fillers without missing anything from the central plot.
Another thing that I think can lead to negative opinions towards the show is the Cartoon Network version of Naruto. Never before have I seen an anime get butchered more by censorship. Also, with American dubs it can look very corny. The characters calling out all of their jutsus would seem very corny if you heard it in English.