i watched this last night and this is what i got:
Buffy: The fear that she caused her parents divorce, her father abandoning her, turning into a vampire, forgetting about a histroy test/not knowing where class is, being buried alive (Which is actually my greatest fear too)
Giles: Getting lost in the stacks, forgetting how to read, failing Buffy
Willow: Stage fright, and i guess spidars could figure into that as well.
Xander: Clowns, public nudity, nazis
Cordelia: MAJOR bad hair day, everyone thinking she's a geek and making her join the chess club.