when someone asked me this my initial reaction was to say the eating one, as i do like my food. But then one of my friends sold me on the benefits of not having to sleep, and much as i love a lie in, i was thinking how cool it would be to have 24 hours at your disposal every day, and how much fun you could have if you didn't have to spend time asleep.
i think i would choose the sleeping one if i could still sleep if i wanted to.
If I could put "sleeping and generally being lazy in bed" as one of my hobbies on my CV, I would. Needless to say, I'll choose the latter because I want to sleep again LOL.