Bio's
This section is all about heaps of bio's of characters off Dragon Ball Z and will be updated very often.

Sorry that there isnt many at the moment.
Goku
Goku, the son of Bardock, is the first Super Saiyan in over 1000 years. When he was sent to Earth as a baby, he was meant to destroy it but one day he fell into a reveene and hit his head. After that a old man called Gohan took care of him. He has two sons with his wife, Chi Chi, called Gohan and Goten (Gohan is named after the old man that took care of him). He is also the first ever Saiyan to reach Super Saiyan level 3 and is 42 at the end of DBZ.
Gohan
When Dragon Ball Z starts Gohan is aged 5. He is the first son of Goku and Chi Chi and the first Saiyan to go Super Saiyan level 2. Gohan is probably the 2nd most important character in DBZ, as he helps defeat Vegeta when he first arrives on Earth, he was very important in the Garlic Jr saga, he defeated Cell and so on.
Bardock
Bardock, the father of Goku, was haunted by his ability to see into the future. He saw that Freiza was going to destroy planet Vegeta. He was actually very powerful - as he was surpassing Prince Vegeta's power level. When planet Vegeta was being destroyed, and he was dying in the blast, before he dies he saw that his son (Goku) would be the one to defeat Freiza.
Trunks
Trunks is the son of Bulma and Vegeta. He comes from the future to warn Goku about the Androids that will come. In his time, Android 17 & 18 have conqered the world. He also gives Goku a cure for the heart virus he is going to get so that he dosnt die. But Trunks comming back to the past changed many things - there was 5 Androids instead of 2, Goku caught the heart virus later than expected ect. Trunks is very pure hearted, as in the Cell saga he was willing to kill Vegeta (his father) to destroy Cell. It is not confrimed, but, he may be the first Saiyan to ever reach Super Saiyan Level Dai San Dankai.
Cell
Cell is a biotechnological android and has 3 transformations. The first is a insect like stage, the second is more human shape like. The third is the same as the second. He reaches each of these transformations by obsorbing different Adroids. First he obsords Android 17 to become 2nd Stage, then obsorbs Android 18 to become perfect. He proved to be very difficult but was finally destroyed by Gohan in the Cell Games saga.
Goten
Goten is the second son of Goku and Chi Chi. Unlike Gohan, Chi Chi doesnt make him study all the time and trains him instead (so he is actually a bit dumb). Goten actually achives the Super Saiyan level 1 in training without any anger at all. He is alot like his brother and father and makes best friends with Trunks.
Vegeta
Vegeta is a Saiyan Prince, and was named after Planet Vegeta. When he was a boy he was very strong for his age, and his father convinced him that he was going to become a Super Saiyan. He first appears when he and his friend, Nappa, are going to Earth to destroy it and get the Dragon balls. He is defeated by Goku and returns in the Freiza saga tryning to get the Namek Dragonballs and wish for immortality. During the Freiza saga he turns from evil to neutral (sort of) and then inbetween that time until the Buu saga he actually sacrifices himself to save planet Earth. From there on he is not evil anymore.
Vegetto
Vegetto is the form of Goku and Vegeta fused together with the Portarra earings. Vegetto is stronger then eigther Goku or Vegeta (obviously).
Gogeta
Gogeta is also the fused form of Goku and Vegeta, but instead of fusing with the Portarra earings, Gogeta is formed when Goku and Vegeta do the fusion dance.
He is incredibly powerful and effortlessly takes out Janemba in movie 12, and probably would hane done the same thing to Ii Shenron if he werent so cocky.
Freiza
Freiza, one of the strongest naturally born villans in DBZ, has 4 forms. He is ruthless and heartless, and uses fear as a weapon against his enemies. He destroyed planet Vegeta along with all of the Saiyans (except 7 of them) because he was scared of them becoming too strong and killing him. He was thought to be killed by Goku on planet Namek, but over 2 years later he returned to Earth with his father King Cold. There on Earth he was finally killed by Trunks.
Gotenks
Gotenks is the result of Goten and Trunks fusing (using the fusion dance). He looks small but is a power-house. He fights Majin Buu two seperate times and, Unfortunatly, he toys with Buu because of the cockiness from the fusion then defuses before he can destroy Buu.
Pan
Pan is Gohan and Videl's daughter. She plays a very large role in DBGT, and competes in the 28th Tenkaichi Budoukai when she is only five years old, and shows that she definatly has her father's blood in her by wrecking all of her opponents (even Goten). 
Majin Buu
Although he changes many times, Buu was originally created by the magician Bibidi. As a magical weapon, Buu went on planet to planet destroying life. Buu was finally sealed up by Bibidi. Much later, Babidi locates the sphere his father sealed Buu in. He starts to form a very small group of soldiers and begins his quest to resurrect Buu. Lots more years pass and Buu is finally ressurected. He does Babidi bidding and goes on a rampage. Eventually, he kills Babidi, and strikes out on his own. He befriends Hercule and reforms himself. All is well with the world, until a few sick and demented human's  tick him off. Not a good thing..... there goes the universe! (he blows up Earth)