If you want to get a feel for how it all began then play FF1 first. It trully is a classic. However the absolute best FF game out there is FF6. It may not have all that hyped up 3-d stuff, but it's got stunning music, memorable characters, a trully wonderful story, and remarkable gameplay.

After playing one of those two, I would defiently play the other old-school (pre FF7) before continuing in with the new school. You may want to hold FF2 and FF8 last. FF2 is good, but it can aggrivate those who are new to the series with its innovative stat leveling system. FF8, in my oppinion, sucks and might make you dislike the series. Then again... you might like it.

If I were to give an order to the games to play it would be...
FF6, FF1, FF2, FF4, FF5, FF7, FF9, FF10. Play FF8 and FFX-2 only if you trully desire to. If you are really ambitous you can do like me and play FF3j by using a rom and emulator.

But by all means, have fun with the series, decide for yourself which one you like and which ones you don't, and if you need any help, ask away.