Which looks better on a resume? A summer internship vs. a co-op (with a Fortune 500 company)?

I’m currently a CC student in my second semester of my first year in college.

I have no work experience, and not much volunteer hours. I’m looking to transfer to a 4-year university next year in the Fall (August 2017).

While typing this question the answer may seem obvious at first, but the co-op would require me to work 20 hours per week. I’m a full-time student taking 5 classes/16 credits, so this may be a borderline overload. My major is computer science. I just want honest opinions.

Is a co-op worth it? Or would an internship look just as good?

I had a pretty significant internship as a CCC student. I would take whichever position is with a more notable company, it will bring you the most opportunity in the future.