This Messi vs Ronaldo discussion is almost getting old, but it is still fun.
For me, I would pick Ronaldo every day of the week to play for United or in the PL at all, and that tells me (in my deluded head) that he is a more versatile player in that he can play well in all types of leagues, the physical and the technical because he has ample attributes of both.
Messi is a magician with the ball, but let's face it, not the fittest player on the planet - ever seen him without a shirt? Not Ronaldo-esque.
Then we will have the Messi fanboys saying that "There we go again, Ronaldo fanboys talking about physique, but football is so much more than that" And they are right, it is. But as I said, Ronaldo has the full nine yards, just a notch below Messi in terms of technique and agility. Would Ibra be as good if he wasn't big, would Zidane? Would fat-Ronaldo be as good without his insane acceleration, would Henry or Giggs?
Messi may be the better player playing for Barca, but to me, Ronaldo is the better player to play anywhere else - but that is just my opinion.