I second the Fallout 1 and 2 games, IMO the best single player RPGs made. Somewhat humorous, but very dark overall.
In a spiritual sort of way, they were the descendants of Wasteland - I never thought a text based game could be so good. Anyone who played knows what I mean. I don't think it would do well at all today, since the graphics are well, they are pitiful in comparison to even the worst games today. But as far as an overall gaming experience, it was the first game that I spent hours and hours playing, without regard to time.
I haven't played it myself, as I don't have the time, but there's a game called Arcanum that uses a similar character generation format to Fallout - but it's set in a magic/tech world.