Is it possible to install Movie Maker without updating my messenger version (2009), or to revert to the previous version once it's updated?
If none is possible, what's a lightweight and simple video editing program for windows?
I don't blame you for not wanting to update to the new messenger version. But that's no the the thing here.
Have a look at Windows Movie Maker 2.6, the last-but-one version before Windows Live Movie Maker. 2.7 is what came with XP but only 2.6 is avalible as a stand-alone download.
I know that it says for Vista but it runs just fine on XP and 7.