Inter Milan aren't really an attacking team, of course they have their own way of approaching games and getting goals, but they are not the kind of team that holds possession and attacks constantly, they do not have the necessary quality in their squad to do that. Having said that, there's no doubt that Inter would park the bus against City, even most of the best clubs in the world would do that, when you come up against City you have to respect them and accept the fact that they would control most aspects of the game, Inter have to do one thing, defend and wait to hurt City on the counter.
Sure. Inter Milan isn't a typical team that plays very offensively, most Italian teams prefer to play defensively. Moreover, if they play a team with many strong attackers like Man City, they must choose a counter-attack strategy. They will focus on their defense first, they will attack when they have a good chance only. It will be a wrong idea to play offensively against a team like Man City, they will be defeated automatically. 
However, if Man City attackers become frustrated because of Inter strong defense, it will be a chance for Inter to score and win the match. Man City should be busy attacking as much as possible, they may lose focus on their defense. So, there is always a chance for Inter to score if they can use a counter-attack strategy effectively.