Most people would say it is best to create the entire text in another app like Adobe Illustrator or Photoshop, then import that text , scale it untill the width looks ok and just animate it’s position with two keyframes.
You can create a text-layer in AE and animate that, but it’s said to be a slower workflow, especially with very long texts.
there is some discussion as to what the optimal speeds are, but be sure to add some vertical blur to make sure you don’t get frame or interlace-flicker.
definately render using fields !
And do a search on the cow for “rolling credits” or “scroll text”, you might find some more recipes.