NEMESIS was a great game for sure but It wasn't a favorite of mine. I believe it had a tad too much action and was more fast paced. I liked the more "take your time" pace of RE1.
I also liked both the Parasite Eve games a lot and I have both the USA and JPN pressings of both games (I can read Japanese ;) . I liked the second game more than the first because it was less like an RPG (the only game genre I dislike). The first game was a lot like a Final Fantasy game to me and I hated the random encounters.
I love the Silent Hill games and have all of the except Homecoming, Origins, and Shattered Memories. Those games were not "true" SH games to me.
I also have the rare BIO HAZARD Trial Edition for PS1. Those can be had for like $200 on ebay, and it's only a 15 minute demo! I was lucky to get a brand new copy from a friend in Japan for a good price. What makes it special is that it's a trial of the Beta game and there are different gameplay mechanics.
I also have the Silent Hill Trial for the PS1 and they are rare as well, but not nearly as rare as the BIO1 trial.