Even though I’m sure the answer is gonna change after like 10 minutes of thinking, my knee jerk reaction to favorite Anime of all time is probably Baccano! It’s a really unique, short series with a great cast of characters.
Cromartie High School, English dub. Hits a good balance between high-density comedy and a loose enough plot that you really don't need to think to watch and enjoy.
Man that's a hard question to answer. I have so many favorites it's hard to choose. I'll probably think about it after posting this and wanna change my answer but I'll go with FMA or HxH for now.
My default answer to this will always be Yu Yu Hakusho, and always the english dub. One of the few shows I can say without a doubt has a better dub than sub.