Depends on the players you have in the squad. But for inter it would be either 4-3-1-2 (more defensive ) or 4-2-1-2-1( attacking with all of eto'o,milito and balotelli on at the same time).
4 2 2 used to be my favorite. Nowadays i like the variations of the 4 3 3, so 4 1 2 2 1 (would be a bank of 4 at the back, holding midfielder, two centrals and a man upfront) or 4 3 2 1