I think FF7 can be a good introduction to the series, though I don't know if I can say definitively that is a better introduction than some of the earlier games. FF7 was the first Final Fantasy I ever played but know that I have more knowledge of and experience with this game in particular as well as the series as a whole, I think it can be beneficial to start off with one of the earlier games.
Among the earlier games, my recommendations to start with would be FF1, FF4 (originally titled FF2 in its North America release), or FF6 (originally titled FF3 in NA). I picked these because they all are strong games with good story but the systems for how to manage your party's skills and equipment and fight battles are a little more straightforward. FF7 is a game that allows for a great deal of customization, which is great, but it isn't always the best way to be introduced to a series and you can take better of advantage of it if you've played another FF game already and are familiar with the general concepts and rules in the series. This is the same reason I didn't include FF5 among my recommendations to start. To be clear, I highly recommend playing FF5 as it is a great game, but I wouldn't recommend it if you are looking for a good introductory game to the series, at least in terms of complexity of the system.
All that said, I did start on FF7 and became a big fan of the series, so it certainly isn't a bad choice. I can say, however, that I gained a greater appreciation for the game on replays of it after having played some other installments in the series.
"History is the road map and without it there is no way to navigate the future." - George Wunderlich