They're from '93 and '95. I fell in love with them when I was little. 7th Guest is pretty much the software that secured the future of CD-ROM. If you've never played them they're definitely worth the money and your time. That's why 20 years later I'm still tempted to play them again. Great puzzles, amazing atmosphere, and the live action story telling is still fun to experience. I hold it in as high regard as I do Alone in the Dark from the same period. Ah, the days before ESRB ratings. My parents would let me buy any game I wanted as a kid :p
Rumor keeps circulating that the developers are working on a third story in the series. I'd absolutely love to see that.