Whowa guys, it's an old PC but it can run any of the games you told me in good detail. I've tweaked it nicely and all.
Let's see, games... I played Torment, loved it. Played HL2, loved it. Tried playing Arkanum once and didn't really get into it, seemed a bit complicated. As for the rest, good suggestions, I'll check them out, thanks. Keep 'em coming