Why Legolas?

[radagastly]

Welcome to the 'Downs!

If you're referring to the shots I think you're referring to, then I understand your confusion. The gloomy stares at Frodo during the Mirror of Galadriel scene actually refer not to the Scouring of the Shire, but to an earlier scene in Lothlorien. When they first enter the edge of the woods, and are captured by Haldir and his cohorts, Haldir turns to Frodo and says, "You bring great evil here. You can go no further." Galadriel says the same thing inside Frodo's head a little later. Then later, Aragorn and Legolas are trying to persuade Haldir to take them in, to keep them safe from the orcs pursuing from Moria, and Frodo looks around at his companions, and they stare back at him as if it's his fault that they won't be let into safety in Lorien. I think it's meant to show a certain level of guilt and paranoia building in Frodo, a sign that the ring is taking hold of his thoughts. The same shots are repeated in the mirror, and then lead directly into seeing the EYE etc. It was a good idea, that didn't quite work for me. I don't know why.