It's basically a variation of the silver theme. The steps are assuming you don't have the theme service turned on.
1.Open the Run command and type in services.msc
2.Find Themes, double click it and start the service
3.Right click the desktop and choose Properties.
4.Click the Theme tab, click the Theme drop down box and choose Windows XP, click Apply
5.Click the Appearance tab, then under Color Scheme drop down box choose Silver and click OK.
6.Open up Services.msc again and turn OFF Themes.
Viola! You have a much nicer looking windows environment without wasting resources.