Clannad

Clannad is something I would recommend even to a friend who have never watched any kind of anime. There is no need to have a "anime background" in order to enjoy it, it's something everyone, without exceptions, can watch. Despite the genre, age, tastes... There is no gore, violence, profanity, battles... it's just the classical slice-of-life humor mixed with a lovely romance, that proves how strong some stories can be by themselves without any kind of "attractive" or fan-service. 
Do you know anyone who's a little depressed and is now reading some kind of self-help book trying to see the "beauty of life"? Recommend to him/her this anime.

If I were to define this series with one word, I'd say it's "charming". It's an anime to be enjoyed, appreciated. All the aspects of it, including art, soundtrack, characters but specially story.
When we were little, we used to find everything amazing, even the most stupid and simple thing was something amusing. We had a hell of a time with friends, laughing for no reason... But, suddenly it's all gone. 
All those great mementos are now just vague memories and you're stuck in a boring and endless routine. This are the thoughts of our male protagonist, Tomoya Okazaki. And this little fragment from the first scene gives you already an idea of how the story will progress. However these are also thoughts we all have inside of us, and that's why Clannad's story becomes so realistic at some point, because it's close to reality, a reality some people have experienced themselves. 
Don't worry, this sadness isn't the main focus of the story. Clannad is a heartwarming tale. Our protagonist will make many friends along the way, and with them new situations will appear, turning his lonely days into something much more enjoyable, happy, and also mysterious. 
Jun Maeda and the screenwriters from Key did a marvelous job with the development of some points from the story, keeping some surprises hidden until the very end.