Hehe, those aeons are nasty.

This thread that I made myself when I first discovered them may help you.

This guide on the frontsite may also help you:

http://www.eyesonff.com/ff10/darkaeons.shtml

But for a start Break HP limit and Break Damage limits are pretty much essential. If you don't want to fight the aeons and just want to get to the temple you can "cheat" and use Yojimbo to Zanmato them.