The Let's Go games were fairly faithful? They are very easy though, because you get so much XP and it's given to all your pokemon. That might be a good place to start, since it kinda holds your hand.

As far as which is the best version, it's usually the last game from that generation. So: Yellow, Crystal, Emerald, Platinum... After that it doesn't matter which game you pick.

Keep in mind there is not a huge difference between the "regular" pokemon games (like red and blue) vs the 3rd release (yellow). The story is the same. They add a couple extra scene at the end and an extra legendary. That's it. For instance, it's not worth getting platinum if you already have diamond.

I would suggest yellow as a good place to start. Having Pikachu follow you around is cute, and by far the best gimmick added to a third game. Plus Jessie and James from the anime are added in a couple places. It's also less buggy than red or blue.

Anything DS or older is very easy to emulate on your phone, btw. I can elaborate on that if you wish.