The last boss was lame, but I didn't think the ending was so bad... my fav FF ending is in Final Fantasy VII...

Though... ranking up there for "Most dissapointing endings" Fatal Frame and MGS2... Fatal Frame had embarassingly bad voice acting and a kinda not scary ending... And MGS2 just lost all sense of reality in the last 30 minutes of gameplay...

Final Fantasy Tactics for the PS1 had a bad ending too....

There's only a few games that had completely satifying endings for me... Einhander, Jumping Flash 2, Xenogears/saga, and Zelda: Windwaker are ones that come to mind...