As someone who started with gen 1 and played all the way through, I can safely say gen 1 was really pretty terrible compared to later entries. The plot is bare bones, you play inventory management puzzles, and the game never tells you what any of the moves do. Gen 2 was an improvement over that, and gen 3 was an improvement over that, and so on. Each gen builds off the other mechanically, so the question is what do you want out of the series? Because you'll have to relearn things for each new generation, so that's something that should be considered if starting with an older game. Honestly, while I enjoyed each game in the series, I don't see a reason to play the older games for other than for the story, as gameplay wise, the latest generation has always been the best option.
