The Steam releases of original Myst and Riven are the ScummVM ports, which work great on modern hardware. You'll find it as "Myst: Masterpiece Edition". Masterpiece Edition is effectively the same as the original release, but with better color fidelity on the visuals. I think the one downside of Masterpiece Edition is that some of the audio tracks were cut short to fit on the CD. Still, I'd say the Steam release is definitely the most hassle-free way of playing the game today.
