Silent Hill...one of the very few video games that I can think of that was actually scary. Resident evil for me wasn't really scary but don't get me wrong I love those as well. Silent Hill is very different from most horror games and it's extremely graphic and disturbing. What set it apart from most other horror games was the exploration of a fog filled town, trying to get to your objective with very few ressources and weaponry. Your alone in almost every game, almost all the time. You rarely encounter anyone and when you do, you can immediatly tell that they most aren't completely sane...
As the series aged and progressed through time, there were some things that changed for the worse and somethings that kept being repeated and made the series somewhat predictable now. In all games except the 4th, you have a radio which emits static sounds whenever enemies are nearby. That means that you know when to expect to be attacked, which to me removed some of the fear unlike in RE where there were more then a few instances where you were suddenly and unexpectidly attacked. Some of the levels were re-used over and over in some games, so once you memorized it, you didn't have too much of a problem in the next game. All in all though, it is a series that no horror fan should miss and nowadays if you find a copy of any of these games there most likely gonna be around 10-15$. I highly recommend them (except the 4th, which I hated)
Silent Hill 1 intro and gameplay:
Silent Hill 2 intro and gameplay:
Silent Hill 3 intro and gamplay:
Silent Hill 4 intro and gameplay:
Silent Hill Origins intro and gameplay:
Silent Hill 5 intro and gameplay: