My votes will be among the most unpopular, but hey it's all for discussion and debate:
1. Naruto - He's freaking irritating! Thank God he learned how to do another jutsu other than the same old Shadow Clone bit. I'm so sick of it. Even then he's so dependent on Jiraiya and others to teach him and work with all the time. Go out and learn how to hone your skills for once, like Neji.
2. Choji - I know that fat people need love also, but can he actually have a better skill set. I don't know who has a worse set of techniques between him and Ino. He is pretty much dependent on those pills and by taking those his life is always in peril.
3. Kabuto - Can anyone say leech? What a lackey, a prime example of a guy that kisses up to upper management to get over. He's your typical brown-noser when it comes to anything dealing with Orochimaru.
4. Ino - Very much like Choji, her skill set is by far the weakest of all the ninja, well there is Tenten but she's not on the list. When you need someone to hold the person you are attacking or for the person you are attacking to stand still; so you can use your technique on them something is incredible wrong. You know you are in trouble when you decide that your fighting skills are horrible and the best move for you is to drop everything and learn how to be a medical nin.
5. Itachi - Oh boy this is going to ruffle plenty of feathers. Yes, Itachi is among the most annoying. The sharingan has unlimited potential: Kakashi is known as the copy ninja so he has copied 100's perhaps 1000's of jutsus. Sasuke has grown the most with his sharingan, with being able to defeat Orochimaru and Deidara, and he's learning new techniques to perform like the chidori current. Outside of killing his own family for power, Itachi doesn't seem bent on killing anyone, he's rather indifferent.