Does it matter which hole you jump into?

Well not really because you go to the same place and if you jumped in a hole you can always jump into a different one afterwards by talking to Brother on the airship (thats how you get a garment grid I forget which one) but I think the only differences are the aeon scenes and like how you get there.

Like I think a temple has if you step on a flame too many times you are teleported back to where you were and another has push the islands into the others to form a path.

But that's the only differences, you still will fight the same people & get to the same place.

No it doesn't. You have to jump into all of them to get the megiddo garment grid though

No it really doesn't matter which one you jump into, but to get the MEGIDDO Garment Grid which lets you cast any black magic spells your party has learned, and you can also cast Flare and Ultima by activating the required nodes. I have at least one character equipped with this Garment Grid. Anyway let me get to the point. If you jump into every hole as follows ( and make it through every one, don't worry you only have to fight the aeons one time ) first jump into the Besaid hole, then Kilika, then Djose, then Bevelle, and finally the Calm Lands hole. After making your way through all 5, at the end will be a chest with the MEGIDDO Garment Grid in it. Hope I helped.