Where to start for an intimidated beginner? (Ideally PSX or PS2)

I bought Scarlet Grace some time ago, but was going through an anxious time and the lack of direction made it a struggle to keep playing. I really love the idea of the series. The mechanical depth, freedom of choice, art-style and general historical value have it high-up in my backlog, but I'm pretty nervous to try another game.

Most of my gaming lately has been on PSX or PS2 emulators. Are any of the games available on those systems fairly accessible (mechanically) and worth playing? I do my best to buy my games and emulate legally, but I'll still take a recommendation if the game is particularly rare or expensive. If I like it, I'll get around to buying it eventually.