The key against Real, in any match, for me is, how well teams make their midfield compact. This was showed by Barca in Bernabeau. This means giving minimal time on settling the ball, and space. Once Real comes anywhere near penalty box then you are punished because they have such good movement and technique that they can pick that killer pass whenever they want. This depends on how you can outnumber Real in the middle of park, and out-hussel Flavio, and Makelele. Also, I feel it is important for Neved and Del Piero to move wide, and get that space which is created by lack of cover by two Real wingers, and adventurous nature of two full-backs.
Furthermore, one of two CB, has to pick up the movement of Ronaldo. There must not concede an inch of space, be it zonal or man-marking. Playing Pessetto, or Tudor, as a man-marker for Zizou could be good idea.