If you already have WinXP SP2 installed
and do not have Movie Maker 2.1...you
could try reinstalling SP2 or possibly the
following article would be useful:
What can I do if I upgrade to Windows
XP SP2 and Windows Movie Maker 2.1
is not installed successfully? http://tinyurl.com/65pfo
If you could use Movie Maker 2.0, you can
download it from the following site.