computer settings help

I know some of you are good at computers.  My son got on the computer again and I can't click on links or icons without clicking on the blue task bar on the bottom of the screen first.  What did he do and how do I fix it?   Thanks.  
Oh, and I also lost my ability to scroll down with the wheel on the mouse.

 

I use Firefox, I've tried restarting the computer and leaving it off for a minute or so. None of the mouse settings/poperties itself has anything to do with my problem. It still says that it's functioning fine.

If I click on the blue menu/task bar, I can use the mouse normally between 10 to 30 secs then the whole browser itself can't be clicked on. It's like clicking on the task bar resets the browser.

 

I.E. works fine.  Firefox started to go crazy on me so I gave up and going to delete and reinstall.