Dead Set was very well-written and had a few genuinely likable characters in it and was, from a plot standpoint, extremely interesting, but I had trouble sleeping afterward and couldn't stop noticing things like my dorm room having a big freaking glass window on the outside-facing wall which would be the least effective protection ever and, yeah, the story is not for people who do not like being depressed. The only zombie story I can 100% recommend to us wimps is Zombieland, which is not only very funny but surprisingly happy for a story where the vast majority of the earth is overrun by the undead. It is unrelated to Charlie Brooker, though, so maybe it is not as relevant to your interests.