The targets of Iname, Life Aspect’s ability are chosen when the ability is put onto the stack, but you don’t choose whether to exile Iname, Life Aspect until the ability resolves.

You may target Iname, Life Aspect. However, this doesn’t do anything since the card will no longer be in your graveyard when the creature cards are returned to your hand.

You can exile the card even if you choose no targets.

In a Commander game, you may send Iname to the Command Zone instead of exiling it during the resolution of its ability. If you do, its ability still works. Iname’s ability only requires that you attempted to exile it, not that it actually gets to the exile zone. This is similar to how destroying a creature (with, for example, Rest in Peace) doesn’t necessarily ensure that creature will end up in the graveyard; it just so happens that the action of exiling something and the exile zone both use the same word: “exile".