It's one of those questions where there is no definitive answer!!
Rooney is an excellent player, superb technically, powerful, works very very hard for the team (tackles back all the time). He now seems to have curbed the anger/frustation and now channels that into his game. However, still a bit of raw talent (possibly picture opp. for this months competition
Ronaldinho - quality player, all the flicks and tricks, scores goals, lacking in his actual team play, i.e can be a bit hit or miss, more so that Rooney. He has the "skills to pay the bills" as they say but lacks the power and directness of rooney.
Both players have their own unique credentials. It is one regret as a football fan that Man Utd did not pay the £12million to get him to united in 2002/3 season and we could have potentially witnessed them playing together!!!
If i had to pick one, as if my life depended on it, i would probably say rooney due to his potential to be a bit more of a team player. That's only my opinion by the way!