If you don't mind old old games , i can recommend
The Legacy : Realm of Terror , good atmosphere but quite tough and the multiple windows can be a pain and the interface is clumsy. Probably freeware by now since the company closed down years ago. If you don't mind the old blocky graphics , it's worth a look.
http://www.mobygames.com/game/dos/le...ealm-of-terror
http://en.wikipedia.org/wiki/The_Leg...ealm_of_Terror
Realm of the Haunting was also very good , a mixture of 3d shooter & adventure but it's nevertheless , a rather unique game that has a good atmosphere but like legacy , it has old blocky graphics.
http://www.mobygames.com/game/dos/re...f-the-haunting
http://en.wikipedia.org/wiki/Realms_of_the_haunting
http://www.youtube.com/watch?v=axwejCPEQMo
