Is Dead Space a horror game with action, adventure, and 3rd Person Shooter elements or is it mainly a 3rd Person Shooter with the aforementioned elements? This identity crisis actually gives this game an extra edge just as you have no idea what is happening on this ship. Everything is constantly in question and you only have only yourself and your handy upgradeable weapons to rely on.
Dead Space delivers exactly what the feeling would be like on a giant derelict ship. The atmosphere is what makes this game stand out. It isn't overly creepy, but keeps you on edge. It does perfectly what movies can't do and that is immerse you in that environment where you could be that person that blatantly walks into the death trap. Tread lightly and keep your plasma cutter pointed forward.
There are plenty of save points and the game never becomes overly difficult. The story unfolds at a clean pace and the upgradeable armor/weapons allow for steady progress. The story never feels too long and the story isn't marred with long cutscenes like most games nowadays.
I am not a big fan of the horror genre, but this game was the real deal.