In Windows XP SP2, after uninstalling WindowBlinds Enhanced 4.50, Windows Classic Style (no visual style, in fact) is the only one that can be choosen from list. Any attempt to choose any available Windows XP Visual Style (ie, Windows XP's Style) leads to an endless switching cycle that never finishes (a hang up in practice) forcing the user to hard reset the computer.
Windows Themeing Service is not disabled nor shutdown at any moment, thus WBE 4.50 uninstall procedure could be messing up the Registry or Windows XP itself.
Anyone could suggest a workaround not involving Windows XP re-installation?