Gohan
Son of Goku,Gohan is 1/2 saiyan. Grows up to become the Super Hero known has Saiya-Man. He is killed in Dark Future(lead to Trunks going SSJ for the first time) but is alive and well after the Dark Future was fixed. He grows up and Marries Videl.

Goku
He is the main character of the dragonball series. He is from the planet vegeta but he came to earth when he was very young and he was raised Gohan Sr.(gohan's grandfather)he grows and trains to become the universes greatest warrior.

Goten
is Goku's second child. He is best friends with Chibi Trunks.

Gotenks
is the fusion between Goten and Chibi Trunks using the fusion dance. He is able to achieve SSJ level 3

Guldo
is part of the Ginyu force. Killed by Vegeta

Janemba
is created when all that is evil is released. Goku defeats the first form of Janemba by going Super Saiyan Level 3. Goku cannot beat the second form alone so he fuses with Vegeta to make Gogeta and defeats form 2 janemba.

Jeice
is part of the Ginyu force, Partners with Berter. Killed by Freiza.

King Kai
North Galaxy's guardian. Trains Goku and the Z Fighters in the second dimension.

Kaioh-shin
This Blood line are gaurdians of the universe. They are practically gods. There are not very powerful but the are very informed and play a big part in the protection of our universe.

Kami
Kami is Guardian of the Earth,Good half of Piccolo

King Vegeta
Is the father of Vegeta. King of Planet Vegeta. He is destroyed by Freiza on his ship with Planet Vegeta trying to revolt against Freiza.

Korin
Korin Gaurdian and grower of senzu beans

Krillin
Human who trains with Goku under Master Roshi. Goku and Krillin become best friends. His death lead to Goku going Super Saiyan for the first time. He was wished back to life later on.

Mr. Satan
Winner of the Strongest under the heavens tournament under Goku. He is a big bluff. He makes earths people think that he is the strongest man in the universe. Father of Videl

Nail
Namek's strongest fighter. He is defeated by Freiza and he then fuses with Piccolo.

Nappa
One of the last Saiyans. He and Vegeta come to earth for the Dragonballs. After Goku defeats Nappa, Vegeta destroys him.

Namekian Dragon
Summoned by the 7 Namekian Dragonballs he can grant any 3 wishes.

Oolong
Friend of all the good guys, Oolong is a shape shifter but he is also a coward. He sticks around with Master Roshi and tries to keep him out of trouble.

Ox-King
Largest human and father to Chi-chi. He used to fight back in his younger years. No he just hangs around Chi-chi

Pan
Daughter of Gohan, she is a 1/4 saiyan. She is loyal to her grandfather and plays a big part in DBGT

Piccolo
My personal favorite character. A namek who grew up on earth and was Goku's sworn enemy but things change. He is around through most of the DBGT series but gets killed and goes to hell. He is still good at heart though