Laptop icon & trackpad problems

My 1540 Vostro trackpad has stopped working properly.

It is often slow, or doesn't work properly and the cursor icon often changes its design - sometimes to and sometimes a horizontal version. I have never seen this before, and can't get rid of it.

I have tried re-setting the trackpad preferences, re-installing the driver, doing a Restore - nothing works.

Sometimes the trackpad's fine, sometimes it is slow.

Is there any way to fix this and stop the cursor icon from changing when I'm using Windows 7.