Stuck in what I think is early in the second half of Wind Waker, sailing the open seas for any clue for entering these two new temples (just some town gossip thus far) and to find Triforce shards and charts (one thus far). Good times. This Zelda game is easy in terms of action, but really open and ballsy in design. Finally playing this was a good decision.
I'm just going to leave this here in code so that you can refer to it if you need to:
You need to get the Cyclone melody so that you can use it to fast travel into the center of the larger of the Mother Child Islands to receive the Fire&Ice Arrows. Once you have them you can open up the Fire and Ice islands to retrieve the Power Bracelets and the Iron Boots to open up the passageways to the temples. You also need to visit both Dragon Roost Island and Forest Haven to get either the bird girl or the tree boy to come with you to their respective dungeons (I believe you must first clear the way before the game tells you to go pick up the one needed for that dungeon; either that or you need to visit them first and then they'll lead you to the proper island).