I want to learn to play faster songs. For example, I can play the beginning of Rach's Prelude in C# minor, but I'm having trouble with the "Agitato" section. My fingers just can't move like that; they get all caught up in between keys. To avoid this, I generally play slow to moderate songs, but I really love that prelude and want to get better so that I can finish it. I do Hanon exercises in different keys, but that doesn't seem to be helping much.
Any advice?

my teacher always tells me to do scales...they suck but they do help you move faster.