Sony Vaio - Keyboard cursor moving all over screen after repair

I have a 4 year old Sony Vaio. Recently I installed an Adobe Acrobat Update which automatically downloaded McAfee Anti Virus. I de-installed that and the laptop wouldn't turn off subsequently so I did a successful start-up repair.

Since the start-up repair the keyboard cursor is intermittently jumping all over the place. It is not confined to any particularly key on the keyboard:- it will jump back a sentence; it will highlight a sentence; it will delete something by jumping to the undo button.

I have not had this problem before. I really do not want to use a mouse as I prefer the touchpad

Do a System Restore to a point before the problem began, if necessary from System Recovery Options on the Win7 disk or System Repair Disk

If this is the original factory install then I'd seriously consider doing a Clean Reinstall - Factory OEM Windows 7 since the factory install is the worst possible install of Win7 one can have, larded with bloatware and duplicate utilities which interfere with better versions built into Win7.

At the minimum I'd Clean Up Factory Bloatware especially turning off all Startup items in msconfig except your AV which ideally should be one of the free lightweight ones like MSE or free Panda.