the "best of..." (w/the white cover) is definitely the "folk" guy.
here's a quick, side by side comparison:
james taylor #1--american, sings and plays guitar, covers classic soul for
mainly baby-boomer audience, losing hair...
james taylor #2--english, plays organ, covers classic spy themes for mainly
gen x audience, losing hair, probably young enough to be
#1's son...
t-bird