I haven't played all of them, but I'l throw out what I already know:
Games I've Beaten:
Myst Masterpiece Edition - 3/5. The best one to start out with, probably, and I like the point-and-click gameplay. Story and gameplay wise, though, it is the weakest of the series. It doesn't include the Rime Age, though, so it has even less of an ending. Also, while the pre-rendered graphics look a little cleaner than realMyst, the textures aren't as nice and the resolution is bad, making the game look worse than realmyst.
Realmyst - 4/5. Same Story and Puzzles, but includes a new age which offers a slightly better lead-in to riven. The graphics feel like graphics rather than real places, although they look pretty good if you crank it up on a modern computer. A better version of Myst, but still not the series' hih point.
Riven - 5/5. While the resolution is low like the original Myst, the graphics are so nice it doesn't look bad at all. Everything in Riven looks so real that the resolution can be forgiven. Much more story, character interaction, and better puzzle integration in Riven. Best of the Myst game's I've played so far.
Myst III - 4/5. Graphics look great, although I'm not crazy about the 360 degree controls Presto used (It's better than what they used for The Journeyman Project 3, but it still looks a little worse than Riven). Cool ages and a great story, although the "hub to age" feel is a step back from the total non linearity of Riven.
Myst IV - 4/5. I haven't completed this one, but the graphics are amazing. This is the Myst game that looks the most real. I'm not a big fan about some of the puzzles, and some of the ages aren't my cup of tea, but it looks and sounds better than ever. And anything with Peter Gabriel is good in my book.
I haven't played enough of Uru, Myst V, or Myst Online to comment, other than that the real-time graphics really didn't impress me when they came out. Now that computers have improved and I can run them at "amazingly best" settings, they look pretty good for their time - I'd say End of Ages compares to a PC game released around 2010 or so. But at the time I had thought it was a huge step downward in quality.
In regards to using wallkthroughs, Myst gets complicated. Using a walkthrough the entire time ruins it but being stuck on a puzzle and going crazy for a week can bug you too. My advice is this:
Take a bunch of notes. If anything even seems like it could be important, note it down.
Try to play the game yourself (without a walkthrough) and if you get to a puzzle you can't solve, continue trying for two or three days. If at that point you still can't solve it and its making you want to abandon the game, get a walkthrough or hint and then close out of the walkthrough and continue on. Don't keep the walkthrough up in another window or your phone or something as you will not be able to resist the urge to look the minute you get stuck.
Post edited December 20, 2012 by DrNilesCrane