I'm going to go with The White Stripes for a couple reasons:
-They spearheaded the garage rock revival scene, possibly the most discernible musical scene of the 00's. They're also the most recognizable of the bunch
-Their 'back-to-basics' approach was a lot more authentic then groups like The Strokes, Jack had a more unique vocal delivery, the lack of bass was an interesting addition (or subtraction, amirite?)
-They released three nearly flawless albums in quick succession
-They had an image:
and variety in sound