Final Fantasy XIV - 146 days, 22 hours and 28 minutes, so 3,526 hours.
Final Fantasy XI - 62 days, 22 hours, so 1,510 hours. I never even did end game stuff or grinded much. Logged in for the first time in about a year to check this. The movement speed has been increased a ton, it's crazy fast. Also the sound doesn't work for some reason. The UI is also impossible to read on my 4K TV because it's the size of a postage stamp. Oh well. I'm not really playing it anymore anyway.
Final Fantasy X-2 - Around 217 hours including my 100% playthrough, my 100% Creature Creator playthrough, and my Last Mission playthrough. If we're counting all the time I've ever pent on the game, I did a previous 100% playthrough on PS2, and a second quick playthrough a few years later. At least another 100 hours.
Final Fantasy XII - 210 hours for a single 100% playthrough.
Final Fantasy XV - Going on 200 hours with all the DLC and it just keeps coming.
Final Fantasy X - I've done 2 100% playthroughs of the international version that both ran over 150 hours I think, and a playthrough of the original where I did everything except the monster arena. I've probably put a good 400 hours into it.
DDR - I have no idea. It consumed my life for about 5 years though and I regularly practiced for 6 hours a day for months on end. I've probably played this even more than FFXIV if you subtract all the AFK time. A good couple thousand hours at least.
Ocarina of Time - I used to just play this over and over and over when I was a kid, so it's gotta be up there. I stopped counting after I beat it the 50th time. I usually averaged 6-7 hours per playthrough. My first several were a lot slower.