Vejiita -Prince of the Saiya-jin, appears after the death of Raditz. He comes with Nappa to Earth in an attempt to gain immortality by wishing it to Shen-long after hearing that Radditz has died. He appears first with brown hair (in the anime) and slightly different looks, but after a year, when he comes to earth, his looks are already the same as those that we see for the rest of the series. Vejiita seems to be about 10 years old in his 1-year space journey.
Goku easily defeats Nappa, but a big battle unfolds between Goku and Vegeta. Goku realizes the strength of his opponent and uses his newly learned Kaiouken. Vegeta, on the other hand, is enraged that a lower-level warrior like Goku can put up such a good fight. This major battle, which was, I'd say, well sequenced and excellently portrayed in the manga, ends up nearly in a draw. Goku, who fights to his limits, pushes Vegeta into using the big ape form. This is a major blow to Goku (literally). However, the fight ends up nearly tied, as Yajirobe daringly slices Vegeta's tail off (this returns the ape back to normal) and as Gohan turns into a giant ape and falls on top of Vegeta.
Vejiita finally joins Goku and friends but never gets to be a real allie; his only purpose in life is to defeat Goku and prove that he is stronger.
During the series he slightly settles down with Bulma having with her two kids: Trunks and Bura/Bra.
Vegeta is driven by the incessant desire to become stronger than Goku, who always seems to be a step ahead of him. Proud and adamant, he will not allow anyone to be more powerful than he is; after all, he is the prince. Like Goku, the Saiyajin blood in him makes him crave fighting.
However, being with Goku and his friends changes him. Once full of pure evil, his black heart becomes diluted into a shade of gray. He shows signs of affection to his son, Trunks, when they are training in the gravity room at Capsule Corp. headquarters. (He promises to take him to an amusement park)
But, apparently, there is a violent conflict deep down inside him; he tries to deal with his inherent evil and his acquired goodness (hey you psych majors -the cognitive dissonance musta been great). This conflict plays out in the Buu Episodes, when Vegeta willingly submits to Babidi's trance in order to clear his conscience and fight Goku as an evil enemy as he was way back when.
But, Goku sees through Vegeta's antics and knows that Vegeta will never be able to return to the pure evil that he once was. Goku is right; Vegeta stops his battle with him and fights Buu instead. For the first time in his life, he fights for a cause that is not his own. Shortly before he self explodes to destroy Buu, he puts his hand on Trunks and tells him his last words and regards for his wife Bulma.
Vegeta is later revived in order to help Goku fight Buu, and they fuse through Potara into the warrior, Vegetto. In the end, Vegeta relinquishes his evil (or most of it) and stymies his pride when he calls Goku the number one warrior. In the epilogue, we find out that he has a second child, Bra.
