The original F.E.A.R. is decent, but I thought that the pace of the game was slow, and even though it's a first-person-shooter it's far from being just a shooter in which you get all the action in so many others of the genre, combat is very localized and scripted, it's heavily story-driven and mostly predictable, at one point you start knowing the "patterns" of the "flashbacks", as soon as you walk in some strange barely lit corridor without a single enemy you know you'll have some vision of some sort.
But, overall, it's decent, nothing mind-blowing, I liked it enough to complete it one time, then I never touched it ever since (I bought it the same week of its release). I must say that the A.I was very impressive however, I'm sure it still is even to this day.