Gintama all the way, check this link to give you an idea of its humor:
http://funnymama.com/post/117089?utm_source=mgid&utm_medium=cpc&utm_campaign=funnymama
I also recalled laughing myself silly when I watched Mahoujin guru guru but that's because it's a satire of the RPG genre
Lastly, I would recommend Astro fighter sunred which is another parody that focuses on the power ranger genre
- samo likes this