How do you change the macbook theme to the original?

a while back i installed an application that changed the theme of the macbook so i liked it and then after a while i stop liking it so now i wanna change it back to the way it was but i cant cause i dont remember the application so is there any way i can just reset it so it goes back to normal without losing my files ?How do you change the macbook theme to the original?
I checked over to the MAC OS HELP menu and it reads, ';You can change the overall look of Mac OS X in several ways. For example, you can change the color scheme used by Mac OS X for buttons, menus, and windows. You can also choose where scroll bars appear in windows or how fonts are smoothed on the screen.



- Choose Apple menu %26gt; System Preferences and click Appearance.

- Choose a color from the Appearance or Highlight Color pop-up menu to make general system color changes. ';Blue'; was the original Appearance.

- Select one of the ';Place scroll arrows'; options to change where scroll arrows appear in Finder and other application windows.

- To fine-tune the way text looks on your screen, choose an option from the Font Smoothing Style pop-up menu.



Depending on the type of display you have, you may notice only small or no differences between smoothing styles.



- If you plan to use small font sizes in your documents, choose a font size from the ';Turn off text smoothing for font sizes'; pop-up menu.



When text smoothing (or ';antialiasing';) is on, smaller fonts can be harder to read.



You can also use other Appearance settings to change the number of items in the Recent Items menu and the behavior of scroll bars and window title bars.';