I can't speak about SH 3 and 4, but 1 and 2 are incredibly terrifying games. After I played the first one I had nightmares. The second one, well... just read what Kishi wrote.

The Resi games have their moments but in this day and age, they're just too cheesy to be effective.

Fatal Frame hasn't been mentioned yet. It's certainly got its moments, though it's not on a par with Silent Hill or anything.

I have high hopes for Alan Wake, though it's not survival horror per se.