That said, X is by far the easiest to get into. Everything is explained in or near the beginning, the path is very linear so you'll have a hard time getting lost, and it's not all that difficult to complete.
Seeing as you already have X though, I would recommend trying out VIII. It also has built-in gameplay tutorials, and since it's not dependent on level you don't have to spend hours fighting random enemies. You don't even have to be good at junctioning - just using the auto-junction feature will get you through almost the entire game. It's really an underrated game because it's actually quite easy to play, but the real draw is the story anyways.
IX is good for the more classic FF feel and it too is easy to get through with a minimum of effort. A bit of leveling every now and then is about all you'll need. The battle system is very easy to understand.
I, II, IV, V, and VI are on the harder side of the scale and I would only recommend them after playing the newer games. VII I'll only recommend after playing some of the other FF games. I honestly don't feel that it's a good starter game because of the rabid fanboy/girl side effects it seems to have on people, and it can be on the confusing side for first-timers anyways. It's also more time consuming in terms of leveling and being prepared for some of the boss fights, so a lot more patience is needed with this one.
All in all it's preference since no FF is better than another. The bottom line is to pick the one that looks fun to you and if you need help with it, that's what these forums are for hehe.
