ok so I did something that made that top part go away and now everytime I want to exit Excel, I have to go to File, Exit. I used to just be able to click on the X at the right hand corner of the screen, but now I have to go to File then Exit. Help!!

In Excel, hold down ALT and the spacebar at the same time. On the menu that pops up hit restore.

If that doesn't help, the shortcut for closing any program is ALT F4

did you drag it too far up.. if so right click on it on the toolbar and click maximize.