On my laptop using the little navigating bit for the cursor but for some reason it's just changed on the screen and now instead of the normal singe white arrow it's all black with one arrow pointing to the left, a vertical line in the middle and then another arrow pointing to the right. It will move around when I touch the pad, but won't let me click by tapping on the pad, I have to click the buttons. What have I done and how do I fix it?
The normal why to switch the scroll arrows is by pressing on the mouse wheel (so the center mouse button) and most laptops I've used will emulate that when you press both buttons together.
Try tapping with two fingers on the touchpad in case it's a multi-touch touchpad.