Mouse icon on screen wiggles about on its own making it impossible to use

did someone remove the dongle from the usb port

usually screens will scroll like that if you have accidentally pushed down on the middle mouse button - you will see a circle with a double ended arrow in it. Moving the mouse in any direction will make the page scroll up or down indefinitely until you deactivate the scroll or move your mouse to the centre of the screen where page stops scrolling but is still active.

This problem commonly arises when the Laser mouse is kept on a plain or some unlikely surface. Use a mouse pad. Your problem is solved.

Simply hold your finger on the application icon until all of the icons start to wiggle. Then slide your finger across the phone holding it in the direction of your home screen. Once you have moved the application to the home screen release your finger.

here is a tutorial

http://www.youtube.com/watch?v=SEbLiQK-7CU

1. Click on the "Start" icon in the lower left corner of the screen. Select "Control Panel." Next select "Mouse" under "Hardware and Sound."
   
2. Select the "Device Settings" tab from the dialog box now. You can see the touchpad for your Vista machine highlighted on this screen. Select "Settings."
3. Read the information provided in the next dialog box. It gives you options for tapping your touchpad, using the buttons, scrolling, pointer motion and sensitivity.
4. Make any changes you want from the various topics. When you make a change, click "Apply." Click "OK" when you finish making all your changes.

This was a common problem that N800's had. From what I've read, requires an lcd replacement.

The light of the optical mouse is used to calculate it's location on the screen. But, if you use the mouse on a shiny surface, it bounces back the signal to the mouse, making it impossible to calculate the position. Use a carpet or else, but not shiny.

hi,there is a setting in mouse options that makes it jump to icons,links,ect if that is on try taking that off
or try updating the mouse driver

hope this helps

If you have a wireless mouse, you may need to replace the batteries inside the mouse. If it is a usb or ps2 mouse (wired), you can first try removing the ball from the bottom of the mouse and making sure you clean the rollers that are inside the mouse. Using a Q-tip works pretty good to remove all the dust buildup.
Second, you can go to the control panel, under printers and other hardware, click on Mouse, and make sure the slider isn't set on 'Fast'. Set it about half way between fast and slow for better control.

sounds like you have two stuck keys. The S key and the TAB key. Suggest that you disassemble keyboard and clean it with alcohol.