FF1: The start-Marsh cave. Once you enter marsh cave the problems with the game become apparant and never get better (or in the 4 gba bonus dungeons case, get worse!)
FF2: Probably Pandemonium just cos I like the music, otherwise i like most of the rest of the game equally.
FF3: Kinda weird but i simultaneously like and hate the end of FF3 The most (well the mini dungeons are slightly worse but eh) I Suppose i will make it simple and choose Eureka.
FF4 As soon as you get to the moon, all the way to the end.
FF5: not sure, after the earth crystal i love every part of the game. Exdeaths castle is cool so i'll choose that.
FF6: Once you obtain the Falcon on the dark world.
FF7: All the parts that take place from the snow up until the weapons awake.
FF8: disc 3 Salt flats- end of disc 3.
FF9: just all of disc 3, sorry it's impossible to pick at that point cos that entire disc is nonstop awesome.
FF10: I have no idea why but my favourite part of 10 is probably when you see the sphere Yuna made cos she was gonna die. I don't usually get too sad at games but that game on my recent playthrough was pretty sad so yeah i choose that part.
FF10-2: Bevelle underground on chapter 2
FF12: does it count if i say going to places you arent supposed to? if not i will say the parimina rift parts (i forgot its name the ice place where you can fight Fafnir hunt)
FF13: Archlyte steppe
FF13-2: Tri-bahamut final boss
LR FF13: Just doing sidequests, basically what i like about majoras mask but for ff.
FF14: Final steps of Faith (story). The Epic of Alexander (Fight)
FF15: seeing Ramuh obliterate all existence.
FFT: the whole part where you fight Weigraf (belias) and Sephirott oh i mean Marquis elmsomething on the roof and the fat tguy gets tossed away.