Movie-wise I was annoyed by Arwen, especially in the 'ranger caught off his' --- no I won't say it!
Book wise, Arwen was a bit of a sook who really only made a banner and sacrificed her immortality (pfft, anyone can do that
) Galadriel, however, was a butt-kicking, intelligent, powerful temptress, who could rebel against the Valar and woo dwarves! The latter being the more impressive and sacrificial...
Anywho, Galadriel all the way.