Superman vs. Goku

Assuming Goku went Super Saiyan right away, probably Goku. Unless Superman went nova like that one spinoff comic... Anyways, Superman's powers(generally recognized) are enhanced senses and strength. He can fly(in Earth's atmosphere), so we can assume this is on Earth. He has laser vision and some other tools. His deadly weakness is Kryptonite.
Now Goku can also fly(calling a cloud), he can fire various types of energy beams, when in Super Saiyan form, he's kind of OP.
CONCLUSION: Unless Superman goes nova, Goku(In Super Saiyan form) would win

 

https://www.youtube.com/watch?v=0MW9Nrg_kZU

(a few naughty words in that video)

They're both nearly infallible (which makes me agree with Goku's slams on Supes in that video), Goku is shown to be more defeatible than Superman. In fact, doesn't he die like eight times? Anyhow, the tides are turned if Goku gets help from kryptonite or a horse (Sorry Reeve, but I totally went there). It's the same reason I don't like the Superman-Batman fight: it all comes down to the single factor of is there / isn't there kryptonite (and why I like the Captain Atom / Superman fight better).

So yeah, I say Superman wins unless there's kryptonite or horses present.