The big difference to movies like 'Paul Blart: Mall Cop' or 'Zookeeper', is that the humor does not result in 'fat guy falls' or 'fat guy has the intellect of a 12 year old', but rather of Fusis naivety and his incapability of social interactions. A lesser movie would make Fusi look like an unsophisticated low life, but Director Dagur Kári still manages to take his character seriously and creates a beautiful character study about an misunderstood, warm-hearted giant.
The numerous comedic elements are skillfully mixed with dramatic components and Gunnar Jónsson conveys all emotions to the audience with his brilliant portrayal of Fusi without relying on a ham fisted, overly emotional score. On the contrary, the score is subtle and fits the cold, but beautiful cinematography of the film.
Sadly, the movie is not without its flaws. The bullies seem more like 6th graders than grown-up men and there is one particular scene that depicts him slightly to naive, which makes him dumber than he actually is.
Nevertheless, these are just minor flaws and don't really hurt the great experience that this movie is.