With its lighting fast fighting, many playable characters and earth shaking attacks, DBZBT2 is a true fighting game.
The story is the same story as DBZ and DBGT except you got 3 'what if' stories. These are non canon stories that technically would change the outcome of the real story in many ways.
SPOILER
1
Raditz gets amnesia and befriends Goku (mistaking him for their father Bardock). He eventually remembers that he's Freeza's henchmen so he attacks everyone and kidnaps Gohan multiple times. Goku eventually defeats him, but since he befriended Goku before all this, Raditz decides to be a hero. He notices Vegeta and Nappa heading towards earth in their escape pods. Since Goku didn't die from fighting Raditz (unlike the true story) Goku didn't get any training from the afterlife, making him UNDER 9000! Raditz reactivates his escape pod and kamikazes into Vegeta and Nappa's pod. Whether he survived or not is unknown, "Only Raditz knows for sure".
2
Zarbon and Dodoria defeat Vegeta, Gohan and Krillin. Vegeta mentions that the dragon balls can grant any wish and giving them to Freeza instead of themselves is idiotic. Zarbon becomes rebellious and tries to kill Dodoria. Then, he attacks Guldo and steals the dragon balls to grant his wish… eternal beauty… what? Freeza attacks him and mentions "Why have eternal beauty when you can have eternal life? You might be beautiful, but you'll be dead". Goku attacks Freeza, not knowing anything about Zarbon. Freeza charges up his Death Ball to destroy the planet. As time is running out, Zarbon steals Goku's spaceship, but gets attacked by Dodoria and Guldo. He kills them both, but doesn't know how to use the spaceship, and Goku's friends used the dragon balls to teleport away from Namek. Having nowhere to run, he gets killed by the planet destroying Death Ball, though is body continues to stay looking beautiful.
3
In short, Goku and his friends destroy Buu before he is revived from the magical ball. Because of this, Vegeta wants Goku to fight him before Goku returns to heaven.
SPOILER ENDS
Other than that, the story mode villains are harder and stronger than they are in vs mode. There are also dragon balls that you can collect to get very powerful items.
What are items? You equip items to characters to increase their abilities. There's health, attack, defense, kai, speed, blast 1, blast 2, ultimate blast and support types, which grant special abilities.
Health is really important, the more health, the longer you can fight.
Attack mostly focuses on punches and kicks, not energy attacks.
Defense decreases damage of the foes' attacks. However, some support items like Master's protection give your immunity to attacks along as you guard yourself, so you don't need defense.
Speed is only useful in story mode because you will be flying around the stage trying to find the dragonball while avoiding certain death from the enemy's attacks. Otherwise, use your speed to run away from foes.
Kai determines your ability to recharge your energy bar and how powerful your kai blasts are. Doesn't effect blast 1, 2, or ultimate attacks in any way.
Blast 1 attacks are abilities that you can use during your fighting. It could be regeneration, charging your energy bar, getting stronger, stunning your opponent, ect. You're blast 1 energy bars are the numbers on the side of your energy bar. The blast 1 bar fills up automatically and when you deflect attacks.
Blast 2 attacks are powerful attacks that you can use at any time as long as you have enough energy. They are beatups (most beatups don't work on giant characters), energy beams, energy balls and others.
Ultimate attacks are available only when you are super charged. They are the strongest attack made by the character. Some of them can destroy the planet you are fighting on.
The best items are Majin seal (villains only), Halo (heroes only), Tenkaichi title and Kiss of Android 18. Majin seal and Halo makes all blast 2 and ultimate attacks cost less energy to perform. Tenkaichi and Kiss of 18 increases all your stats by 4 points.
Now for the characters. Many characters have transformations. Transforming into a stronger form will change your strength. It might increase your size, give you a new energy bar and/or give you a new health bar. Powering down will decrease your strength, but transforming of any kind will effect how your character can charge up energy. Most characters have certain abilities that super charge them, but leave them exhausted. Transforming or powering down makes it easy to regain control over your power. Unless you are powering down, you need a certain number of blast 1 energy bars to transform.
Since there are so many characters, I will only mention certain main characters.
The Ginyu force each have a dancing pose that super charge them, making them use their ultimate attack multiple times. Otherwise, they are normal characters, though each one is unique. Guildo is the joke character, Burter is perfect at combos and Ginyu's ultimate attack makes him change bodies with someone, so that his hp is full, but he can't do blast 1, blast 2 or ultimate attacks.
Hercule is THE joke character of the game. Enough said.
Gogeta ss4 is THE best character in the game. In fact, all fusion characters are more powerful than almost everybody else.
Most robots and cyborgs regenerate energy automatically but at a slow pace. Android 20 and 19 can't charge energy except by fighting. Their grapple is similar to Super 17's and Cell's tail grapple because they all absorb the foe's energy and health.
Giant characters, like big apes, are immune to flitching most of the time and can't be grappled but are slow and can't dodge very well.
Hirudegarn's attacks are the highest (except for his blast 2 and ultimate attacks) and his hp is one of the highest.
Some characters can self destruct. Despite the fact that they lose all their health, these attacks are not the strongest.
Tien's ultimate attack, the Nova Tri-Beam Cannon, is THE strongest attack in the game. As long as Tien has a lot of health, it is almost always an instant ko. However, this does drain Tien's health.
Goku's spirit bomb is the 2nd strongest, but is the hardest to perform. You need to charge it and then attack, hopping that the foe doesn't dodge it.
Gogeta ss4 has the Big Bang Kamehameha X 100, which is the 3rd strongest attack.
But there are some things that people will not like. The one everyone will hate is these characters.
Freeza Soldier (Zeso)
Appule
Piccolo Sr.
Cyborg Tao
Pilaf's battle droid (transforms into - Pilaf, Shu and Mai's super battle droid)
Why are these characters bad news? They are NOT in the American version. Removing ANY content from the American version should be an abomination!
Freeza Soldier can be selected on the same team more than once.
Pilaf's battle droid is a joke character while his transformation, the super droid, is known for firing b00b missiles and crotch missiles.
Now to compare this game with the other BT games.
The first BT game (Dragon Ball Z Budokai Tenkaichi 1) had poor graphics, less characters and was not on the wii. The fighting was dull and having fun with the game was not easy to do. Not a lot of attacks or combos and fighting seemed too simple. Compared to the other two games, this game is terrible. Even the menus are stupid looking. You don't even have optional costumes! The fact that this game is related to BT1 is almost unbelievable if it wasn't for the 3d fighting.
BT3
Graphics are slightly better than BT2, so it doesn't matter that much. The fighting is slightly faster and the amount of moves you can do increase, though it might get annoying if your opponent is always dodging. There are more characters, but most of them are not important, joke characters or are alternate forms of main characters (like Goku during saiyan saga, Goku during freeza saga and Goku during buu saga). Story mode forces you to play at a handicap and not gaining experience for your characters. Story mode does give short cut scenes during fights and having conversations with your opponent, but it might be distracting, depending on what you think. Also, while fighting in story mode, you might get a chance to quickly kill the opponent, making the fight easier. It has less fighting, though you can decide if you want to play as villains, so you can beat up Krillin with Freeza. Attacks from the previous games are changed or replaced by other moves. Also, BT3 has some more stages than BT2, but it's not much of an improvement.
Is this game better? Is it worse? Hard to tell. If you want as many characters as possible with the ability to replace English voice actors with the Japanese ones, despite a weaker story mode and a harder to learn fighting style, buy BT3. If you want a lot of characters with good fighting, story mode but fewer graphic, buy BT2.
Ps, if you have the wii version, NEVER use the wii remote. Use the gamecube or classic controller.
In the end, this game (or BT3) is a must for any DBZ fan.