Are you having trouble when you try to highlight text? You know, when you put your cursor at the point where you want to start highlighting (selecting) the text and drag it across?
Try this, then: put your cursor where you want to start selecting, hold down your SHIFT key and use your up / down arrow keys on your keyboard. You’ll find when you hold down an arrow that the text scrolls (and highlights) at a much more manageable rate.
Oh, if the section is really big, tap your Page Up and Page Down keys till you get close to where you need to stop.