I was kinda bored at first but once the bomb hit and as there sickness grew and at the end with the bags...I almost lost it. It was the combination of music and visuals with the bags, I had to fight back the tears.
Being bored at first is intentional. It allows you to get accustomed to the characters and their routine and normalness and is probably visually mirroring their age and lifestyle (ie. "boring" - as we in the west tend to generally think of old people). It makes the rest of the movie so much more effective due to the contrast in the circumstances that they soon find themselves in. Plus it probably lulled you into thinking it was just going to be a "cartoon" and would not go as far as it does and be as tragic as it was.
That's what I thought when I watched it anyway. When it was over though I realised that it just wouldn't really work without that "boringness" at the start. I'd like to watch it again but it's hard. Although it's brilliant and I love it, it's just so... harrowing.