The Innards of Buu - Vegetto uses a barrier to survive, revealing hed intentionally been swallowed to rescue the others.

Somehow being inside Buu causes Vegetto to defuse.

Vegeta crushes his earring to prevent future fusion.

He and Goku explore Buus stomach and are attacked by a giant worm.

Dende and Mr. Satan hide from Buu, who is ransacking the earth.

Mind Trap - Buu gets indigestion and uses the toilet.

Goku and Vegeta travel to Buus brain and battle Buus memories of Gotenks, Piccolo, and Gohan.

Then Buus thoughts turn to food and sweets appear in the fighters places.

Goku and Vegeta find their friends trapped in cocoons.

Visions of Deadly - Vegeta and Goku free Gohan, Piccolo, Goten, and Trunks, causing Super Buu to revert to the weaker Buu.

Buu figures out whats going on and sends a vision of himself to fight Vegeta and Gohan in his own brain.

This vision seems to be invincible.