Defo not Naruto... He actually does everything for the attention, esteem and respect of others. That's the whole point of his goal to become Hokage. That his what all his actions are aimed at, and that is all about him. So no, I wouldn't put him as selfless at all. Anything he does for someone is still quite intentionally for him in the long run. But it's a good way of getting everyone saved so I'm not complaining. Young Obito is quite similar to Naruto and quite self-absorbed and bratty, but he sucks hard cos unlike Naruto, his behaviour doesn't get the job done and it's now led to the entire world's doom.
Ironically enough, Itachi, who I might think of as the most selfless for killing all his brethren for the safety of his village and his younger brother, is easily the most stupid (or has the most stupid method of getting things done). Because his actions haven't really appropriately got what he ultimately wants/wanted accomplished in the long run. I'm not too sure I'll give him the title because whilst being selfless, he's been quite cruel. Others have managed to be very selfless without massacring whole clans.
Shisui - The way he took that eyeball out for Itachi... Daym, if that's not selfless, I don't know what is.
Hiruzen and Minato - I agree with the comment that they've sacrificed more than just their lives but their afterlives as well for the entire village, and in the case of Minato, the future of his son was sacrificed as well for the entire world and not just the village, so I think I'm going to give it to him.
Sure Jiraiya sacrificed his life for the village and Young Nagato sacrificed a lot for a better future for the Rain Village, but Minato sacrificing his afterlife and children's for his village and the whole world I think wins my vote.