Austrailia representin' with this fix. I've gotten tons of questions about how to get the Windows Media Plugin to work on Windows Vista.
You see, in the install there is a bit of code that checks to see if you are running Windows XP and if you are not (even if it is the next version) it will not install the plugin. I have been working on fix that required me creating me own WMP plugin to basically do what the already created plugin does but only it would install on Vista.
Well, Frank Arrigo has provided a fix for this issue here. The Reader's Digest version is to install the Winter Fun Pack for Windows XP. A different plugin is included that provides the same functionality only this one will install on Vista.