Looking for a good storyline that is both funny and fairly complex? Look no further than Cartoon Network's Adventure Time. It chronicles the exploits of the denizens of the Land of Ooo, focusing primarily on Finn the Human and Jake the Dog (pictured). It's simple enough for children to enjoy but definitely carries adult overtones and jokes to make it enjoyable for a 41 year old man to enjoy (me). You'll recognize a lot of voices from other shows like Jake (John DiMaggio, Futurama's Bender), The Ice King (Tom Kenny, Spongebob Squarepants), and Princess Bubblegum (Hynden Walsh, Teen Titan's Starfire). The other main character, Finn is also pretty well known for both voice (Robin, Batman:The Brave and the Bold) and regular in various tv shows. There's also a lot of other regular, iconic actors lending their voices to it as well such as Lou Ferrigno, Keith David, and Mark Hamill just to name a few.
One of the endearing things to me is the humor. As a male, bathroom humor plays a big part in my life. It also plays a good part in Adventure Time, like a giant fighter named The Farm who defecates farm animals on his vanquished foes or Jake the shapeshifting dog farting on newts who steal boots, apparently they get poots. However, the greatest aspect of this cartoon is the complex intertwining of stories that pretty much spans the whole series, five seasons thus far. From small details like a creepy little waving snail to a history that goes back 1000 years between Marceline the Vampire Queen and Simon the Ice King at the end of some bizarre war that also concerns a weird pink goo that has a suspiciously familiar smile.
The absolute best thing about Adventure Time however is you can either enjoy it at a base level of simple animation with great jokes or take it farther and pay close attention to every detail and get as much out of it as I do. That and it's something I can watch with my 5 and 9 year old daughters that has princesses but doesn't feel emasculating to watch.