Here is a list of Windows XP system files, which can be edited using Resource Hacker to change the look-n-feel of Windows:

%windir%\System32\NToskrnl.exe : To change Windows Boot screen

%windir%\System32\Logonui.exe : To change Windows Login Screen

%windir%\System32\MSgina.dll :

%windir%\System32\Shell32.dll : To change a lot of things, like Progress dialog box (copying, deleting, etc.), Run dialog box, Context menu items, and many other things

%windir%\System32\Netshell.dll : To change flashing internet icon in system tray

%windir%\System32\Comdlg32.dll : To change the look of Open/Save dialog box, color box, print box, find & replace box, etc.

%windir%\System32\Comctl32.dll : To change the icons appearing in upper-right side of Open/Save dialog box.

%windir%\System32\Stobject.dll : To change volume icon & some other icons in system tray

%windir%\System32\mydocs.dll : To change My Documents icon

%windir%\System32\shdocvw.dll : To change Internet Explorer 6 icons and graphics

%windir%\System32\IEFrame.dll : To change Internet Explorer 7 icons and graphics

%windir%\System32\shimgvw.dll : To change image file icons, i.e., BMP, JPG, JPEG, GIF, etc

%windir%\System32\Sysdm.cpl : To change the System Properties window look

%windir%\System32\Winlogon.exe : To change the text, which you see in Login Screen, like applying user settings, logging off, shutting down, etc.

%windir%\Explorer.exe : To change Start button text, Programs Menu text (like Programs, Favorites, Documents, etc.)

%windir%\System32\browselc.dll : To change the Menu names in Windows Explorer as well as Internet Explorer

Windows XP Setup folder\I386\Winntbbu.dll : To change XP Setup look and text entries