As you all know that Windows Vista is slightly different from Windows XP. If you are looking forward to transform your Windows XP into Windows Vista, then you will also need to edit the default windows XP about dialog box. A deviantart user picassa has created a mod

By which you can change windows XP about dialog box into Vista about dialog box, without any software.

Above, was the small preview of this mod, if you are looking forware and willing to taste this mod then you can download the package created by piucassa from the following link:

Get Vista About Dialogue Mod for Windows XP

If you want to transform your Windows XP into Windows Vista then you might want to read: Change Windows XP into Windows Vista without using Customization Packs