If I ever got into Naruto during my younger years, it was definitely because of the opening themes that got me hooked. The same story could be said with my brother and his great love for One Piece. It first started out as awknowledging the theme song and eventually lead to him to scouring the internet to find every volume availible. Naruto I chose to do because out of the “Bigger” names in the manga/anime world today, it currently has the least amoung of songs I like. I guess I just stopped caring for the openings after Shippuden started.
In my very short opinion on Naruto, they should end it after this current arc. Also, WHY ISN’T ANYONE “NAMED” OR “SIGNIFICANT” DYING YET?
So the first song that got me into Naruto was by the 2nd opening, Haruka Kanata by the AKFG.
Lair of the Idle 
I personally think Jiraiya and Itachi are significant characters…and my friend was so sad when Itachi died. He is a very popular character.
I have trouble remembering the OP song I like best for Naruto but the one you mentioned is good. As for Naruto Shippuuden..this is the one I like best -> http://www.youtube.com/watch?v=hafwXo0iKKk&feature=related
I actually stopped caring after both Deidara and Itachi died, I agree that they are signifcant but I just wished more guys on the “good” side would kinda…die off.
Aha, that opening you just linked is actually the very few shippuden themes I remember
I see a lot of people like the good characters dying, I myself would love to see some die, but not one of my favourites. Jiraiya’s death is one of the hardest to accept. His the coolest guy ever in the series, so yeah.. so sad..
As for the OP. Th best song ever for me is this one > http://youtu.be/o8mgCSpKSZ4