Quick psychoanalysis of some of the characters. More will be added. These guys need help!
Gaara - Suffers from paranoia, delusions, and hallucinations. Paranoia is justifiable as his father has attempted numerous assassinations. Delusions and hallucinations involve talking to his "mother" and feeding her blood. The shield of sand, which protects and entombs him like a womb, becomes the manifestation of his deceased mother's love.
Hinata - Inferiority complex perpetuated by a domineering father and a more talented younger sister.
Itachi - Sasuke's older brother committed patricide, matricide, and genocide of the Uchiha clan; signs of sociopathic behavior such as introversion was noted by his father early on.
Jiraiya - One of the legendary sannin (three ninja team) and a sennin (hermit/sage), but since childhood he's been a peeping tom. Now he's 50, lives as a hermit, but comes to town to spy on women in bathhouses as research for his x-rated books ("Make-out Paradise" and "Make Out Violence"). Naruto calls him the perverted hermit. Voyeurism is considered a disorder of sexual arousal. The onset of voyeurism is usually before the age of 15 and tends to be chronic.
Kakashi - His passive-agressive tendencies are exemplified by his chronic lateness, and the way he ignores Gai. His non-conformist attitude is exemplified by his apparent lack of concern of what people think of him as he reads x-rated novels in public, wears his mask all the time, and doesn't talk about himself. (see Kakashi shrine for full analysis)
Naruto - Classic class clown inferiority complex masked by a show of egocentrism. Need for recognition is projected in mischievous behavior.
Neji - Superiority complex tempered by a fatalistic attitude stemming from his bitterness over his father's sacrifice and the Head family's restrictions on the Branch family.
Orochimaru - One of the legendary sannin, but evil! Suffers from the God complex - he literally controls life and death. He uses resurrection techniques, sacrifices his underlings, and seeks immortality for himself. A typical psychotic - he's killed a lot of people, has no conscience, and looks like a total weirdo psycho snake guy!
Sasuke - Superiority complex perpetuated by all those who bow to the Uchiha name. A self-proclaimed avenger consumed by the thought of vengeance against his older brother Itachi. An anti-social loner despite having a bunch of groupies. The trauma of seeing his parents and clan slaughtered by his brother twisted his psyche from a normal child capable of love and laughter to his current persona.
Sakura - As a child suffered from a lack of self confidence, but now that she's older, she's a typical teenager with rebellious tendencies. Because of her past insecurities stemming from bullies picking on her appearance (wide forehead) she looked up to Ino with her stronger personality and became her follower. As she grew older and developed self confidence in large part thanks to Ino, she rebelled against her role as follower and cut her ties with her best friend. The spark that spurred her to this action was their competing feelings for Sasuke.
Shizune - Co-dependent personality; enables Tsunade's additions to gambling and alcohol.
Tsunade - Suffers from survivor's guilt, hemophobia, an addictive personality, and a really bad temper. Since childhood she has had a gambling addition and anger management problems. Since the deaths of her loved ones, she developed a fear of blood despite having been a medical specialist.