..just checking something
Goku is not allowed to move for the first 30 seconds, and he is not allowed to attack for the first 60 seconds.
Does he still wins?
" Yeah but doesn't Goku generally run like heck when a planet buster is on his !@#? "
Let’s try observing entire feat.
First Buu fired planet busting energy ball, and Vegeta easily stopped it.
Then Buu got serious and created far more powerful energy ball and he fired it. The energy ball was too powerful for them to deflect it, and to fast for them to save everyone.
The energy ball exploded and it created explosion of unknown size and intensity. (I guess we could say it's radius was smaller then 8 light minutes, since sun wasn't destroyed)
Since they were unable to deflect it I would say that energy ball was far more powerful then the energy beam SP Cell fired, because they were both far more powerful then SSJ2 Gohan, who was able to deflect SP Cell’s beam.
How powerful do you think second energy ball was?
I admit Goku and Vegeta were acting kind of strange, as if they were afraid of even the normal planet explosion, but that could be because dragon balls were still on earth, and so were their sons, piccolo, satan, and that little namek (den den?).
Gotenks, Gohan Trunks and Piccolo were all KOed and their energy was sucked out, so obviously even a normal planet explosion was a treat to them.
And Frieza survived planet explosion while being cut in half, beaten up, and with very little energy left. If he tanked a planet explosion while at full power, this is what would happen:
He might lose some strength
And he never even questioned Gokus ability to survive the planet explosion, he thought Goku will die after the explosion because he can’t breathe in space. Keep in mind this goku is incomparably less durable then SSJ3 Goku.
So the only question is how long can Goku survive in space, and will he have enough time to kill all Friezas.
I think Goku wins here.