Just plain turned off by the controls? Stick with it.
Let me just say that after playing through the campaign, in a sense, the controls are in a league of their own. As was stated by a developer of the game regarding complaints that players had, the game was not intended to be a twitchy, point and shoot experience, but rather was intended to be immersive and strategic. And immersive and strategic it is. The difficulty in killing an enemy soldier due to the controls is extremely rewarding for several reasons, and the developers should be applauded for taking the risk. The key elements that shape the nature of the firefights in Killzone 2 are cover, combined with the Helghast's seemingly superior aim. This creates immersive firefights in which the player is forced to use wit, patience and the environment as opposed to simply trying to outgun the enemy. The firefights are broken up throughout the game normally into very distinct scenarios which play out the same way on the Helghast side as far as enemy placement and behavior if the player dies and is forced to make another attempt. If the player dies, it isn't because the player simply failed to outgun the enemy. It's because of strategic errors made by the player related to everything from positioning to cover to weapons. This creates extremely engaging firefights which the player can learn to overcome by trying different strategies as opposed to just "shooting harder". While all this may not seem to provide the instant gratification of some other shooters, the gratification you ultimately get from coming out on top in these firefights is far more rewarding. In this game, it may be difficult to pick off a Helghast up on a balcony 50 yards away, but when you do, you feel like you just knocked out someones queen in chess. Patience is a virtue in this game. Don't look for instant gratification. I for one would gladly trade the shallow gratification of running into a firefight blasting enemies with the flick of a joystick for the real gratification that comes from using my mind to overcome the enemy through the use of the environment, strategic thinking and a little patience. All of this creates for an unprecedentedly engaging and immersive FPS experience.
So that covers the gameplay. The rest can be summed up quite easily. The graphics are beautiful and stunning both artistically and technically, although the field of view might be slightly bothersome to some players. The sounds is also excellent and immersive with the only shortcoming being the repetitive speech by both enemies and your allies. The story of the game is nothing special as far as the actual narrative throughout the campaign. The characters are forgettable (except for Sev and Rico). Ultimately I did not find this to be a bother at all because the lack of actual narrative is almost entirely redeemed by the set up of the plot created by the immersive and characteristic environment and the absolutely outstanding opening movie which is probably one of the best I've seen in a game. I watch it nearly every time I turn on the game to set the mood for the conflict I'm about to be dropped into. The ending is also very satisfying. No one can argue that there couldn't have been more in the way of story, but it's very difficult to actually find real fault with it the way it is.
All in all, Killzone 2 is an intense, immersive, thinking man's FPS experience that should not be missed.