I'm pretty sure that the hour glass is not the cause of your slow computer. It could be a lot of reasons why your computer is slow... spyware, too many things at the startup, etc. If the hour glass is always there no matter what you do, please check your mouse settings to see if the hour glass was made your default cursor. Go to START>SETTINGS>CONTROL PANEL>MOUSE. Go to the "Pointers" tab and check what the "Normal Select" mouse is. If it indeed is the hour glass, you can change it.