The Pilaf saga definitely. Toriyama was still in his Dr Slump mindset when writing that. The comedy was just childish and pretty much reused the same gags (haha Yamcha saw Bulma naked by accident...oh look he just did it again in the exact same chapter haha).
Though at least the Pilaf saga knows what it wants to be. The 21st Budokai had a 50/50 mix where half the time it seemed like it wanted to be serious, and half the time it wanted to be a full blown gag manga.