Like what the hell is wrong with all you people. Windows movie maker is just about the most basic, and featureless video editor around. You CANT make professional windows movie maker videos. Almost every single youtube video that has even been partially edited by this crapware has that "movie maker" taste to it, that single color background with an overused text effect going over it.
If you want a good video editor then yes adobe premiere pro cs4 is just about the most advanced, feature rich editor out there, but it takes a while to learn. A possibly even better alternative is cyberlink powerdirector. It's awesome, has everything you ever wanted, and is easy to use. They both cost money tough, but that's why they created torrentz.com