FF14 is a very easy MMO to get into. It'll teach you everything you need to know to play well at a steady pace, and the playerbase is still pretty good. It's fun to play and the story is very enjoyable.
In fact, patch 5.3 (which should be out around this summer) should be making the main story quests a little less tedious, so if you're on the fence I would wait until that comes out.