Why Win2000 or WinXP?
1. Task Manager - which can kill "any" process (for example if BSPlayer get freezed) without need to restart your computer (in Win9x and WinME Task Manager is quite uncapable)
2.
http://www.aumha.org/a/whichwin.php (for more information)
3.
http://www.aumha.org/stats.htm