Before we answer, we must define what dribbling means, cause I see some folks don't actually understand. Dribbling means getting past defenders, regardless of the method one uses. Some use fancy tricks, others keep it simple, some use body feints, other use their athletic qualities. In the end all that matters is the end result, whether you get past opponents or not, not the way in which you do it.
Second of all, we must also take into consideration the number of players one gets past. It's one thing to be able to get past 1 or 2 opponents, it's a whole different ball game when you get past 4 or 5. For instance, as great as Zidane was, he usually got by 1 defender, so he's not exactly among the all time greats when it comes to dribbling.
Third aspect is the difficulty of comparing players from different eras, like some other members pointed out. IMO it's easier to get past opponents nowadays for a top player due to the increased protection he gets from the refs, plus better pitches and equipment.
As good as Messi and CR7 are, they're vastly overrated. They are surrounded by world class players who play for them at their club teams, and the Spanish league isn't exactly famous for defending, so it's not that hard to get the records.
I'm willing to bet they would spend more time on the sidelines than they would on the pitch due to injuries in they were to play in the 80's and 90's, especially in Serie A or Premier League.
Messi has tremendous close control, but put him on a muddy and uneven pitch and he struggles bigtime. Argentina played a friendly against Romania in 2014 and Messi was non-existent. When he was questioned about his poor performance by the media after the match, he blamed the playing conditions.
With those things in mind, I'd have to give the edge to the old legends.
I haven't watched the likes of Pele, Best, Garrincha, Cruyff or Maradona live. There are youtube highlights and they pretty much cover Maradona and Cruyff's career, not so much for the other 3. From the few footage that I've seen though, Garrincha seems vastly overrated. Pele and G. Best look very good, shame only a small part of their career was filmed.
Anyway, given what I've seen, both on film and live, my top 5 would have to be: Maradona, Ronaldo Fenomeno, Pele, Best and Messi. Messi only gets last place cause he has it easier, I don't think he could have replicated his feats in previous eras, due to the ferocity of defenders, and his frailty.
I also have to explain why Ronaldinho didn't make the cut. Although he was a good dribbler himself and a joy to watch with his fancy tricks, he wasn't as effective as these 5.
And we're debating here who the best dribblers were, not who were the best to look at.