Sometimes when I am typing online, say, an email, the cursor will suddenly jump to a different part of the screen and continue writing there- in between another word usually. When I stop and click to find the cursor, a box appears that looks like a drop down menu from internet explorer, even though I am on aol.
My PC has been playing up and crashing- leaving a blue screen with text on it, but I thought this was linked with my failing landline, which has now been fixed. ANY ideas at all??!!
Have you got a wireless mouse? It could be low batteries. Also, my sister used to use a wireless mouse in another room that would always interfere with mine. Very annoying!!!