Uematsu combo! xD 
FFI, FFII, FFIII, FFIV, FFV, FFVI, FFIX:  
"Battle Theme" (only the intro, by Uematsu) and "Battle of Evermore" (Led Zeppelin): 
http://youtube.com/watch?v=SplNqFfSAhc 
 
FFV: 
"To the North Mountain" (Uematsu) and "Fanfare for the Common man" (Emerson, Lake & Palmer): 
http://youtube.com/watch?v=WMtgYccv30U 
 
"Toccata", "Hoedown", "Trilogy" and "Knife Edge", are, among others, songs by ELP that you could hear in a Final Fantasy game...  
FFVI, FFIX: 
"Terra's Theme", "Vamo' alla Flamenco", "Limited Time", "Black Mages Village" (Uematsu) and "La Folia" (unknown composer, more info here:  http://www.folias.nl) But I think the main inspiration for Uematsu was "Conquest of Paradise" (by Vangelis, who also used the Folia chord progression...). 
http://youtube.com/watch?v=ExqC2T232sk 
 
FFVII: 
"Debut" (Uematsu) and "House of the King" (Focus): 
http://youtube.com/watch?v=H2HoM41iZys 
 
 (ignore the video, just listen to the music)FFIX: 
"The Evil Mist's Rebirth" (Uematsu) = "A Salty Dog" (Procol Harum) + "Watcher of the skies" (Genesis) 
http://youtube.com/watch?v=ylzCPwCKn1c 
 
http://youtube.com/watch?v=rq5vFpGD_so 
And the list goes on...