You should get a arrow at the bottom of the screen. Which will allow you to stretch the taskbar upwards to restore it to its original size. After you do this you might consider locking the taskbar in place. To do this you would right click on the start button, then choose Properties. Next click on the Taskbar tab and place a checkmark in the box next to Lock the taskbar. To exit just click OK. I hope this helps
Joop