Hey harris59,
I'm sorry you're running into that issue with the Start button. That whole bar that goes across the bottom is called the Taskbar. It shows you buttons for programs that are running and the time over in the right corner. Do you see any portion of it?
If not, there are two possibilities.
1.) The taskbar has been set to 'hidden'
2.) The screen resolution has been changed.
Put your mouse at the bottom of the screen, right on the edge and see if the taskbar pops up. You may have to leave your mouse there for a second or two for it to come up. If it does, right click on the free space in the middle of it and click Properites.
In Properties, look at the Auto-Hide checkbox. If that is checked, uncheck it.
How do the rest of the icons look on your screen? Do they look normal in size? If not, check your resolution. Let me know if that is the case and I'll provide steps on that as well. :) Hope this helps.