What's the difference between a Full Motion Video and a CGI video?

[Vincent]

Lately been playing some old Final Fantasy games, and sometimes there are 2 types of cutscenes that are pretty distinguishable. One is those videos that are using in game models but has additional effects such as swaying hairs and thick shadows, and the other one is more high quality that shows full 5 fingers instead of fingers that are clumped together.
Not to be confused with in game cutscenes, though.

[novasunshine]

One's from the game's engine and the other one's done with something else.

[Generation X SMURF]

A very good CGI is the osama expulsion to the ocean, its so great and real to the eyes only surpassed by minecraft!!!!

[Commander Makara]

That's not the "diffference bwetween cgi and fmv"

FMV can contain elements of CGI but it isn't necessaary.
CGI may be an entire image or sequence of images, or it may be merely post-proc enhancements of such.

All you're referring to are different artistic styles used to present different sequences.

In FF games, there is no live content, all the FMV sequences are entirely CGI irrespective of the "realism" or stylistic of the visuals.