Vista Transformation Pack
Note: This review addresses v6 of the software.
Like the look of Vista but don't want to switch from XP? Then try out the Vista Transformation Pack. It changes XP's basic interface, including the Start button, the Control Panel, system dialogs, icons, and more, so that XP mimics the look and feel of Vista.
Be aware, though, that the transformation is only skin deep. The program won't give you transparent windows, Vista applets, or other unique features of Vista. You're still running XP; it only looks like Vista.
After you install the program, get that Vista look by right-clicking your Desktop, choosing Properties --> Appearance, and choosing from the "Windows and buttons" drop-down list Windows Aero. To use Vista wallpaper, click the Desktop tab and scroll through the backgrounds. Vista wallpaper will have strange numbers, such as "img19," instead of names.
One caveat: Before using the program, make sure to create a Restore Point, because the installation can be somewhat difficult.