The thing that drew me to Dead Space was the comparison made that it's Resident Evil 4 meets Metroid Prime. It's the best description anyone has ever given the series first game and it applies with the entire series.
The blood stains and the logs and all of that jazz isn't there to scare you, it's there to provide a mystery, what exactly happened to these people? What were their story? How did things get like this? Explore, collect logs, inspect the rooms you come across and find out for yourself.