Windows Live Movie Maker
Full user review
"Terrible timing issues... just sucks."
It installs and uninstalls
Editing timelines is crazy - they move when they shouldn't.
Visual queues are deceiving. A piece that last .5 seconds will look the same as a piece that last 5 seconds in the storyline / storyboard / whatever the place where you see the video is.
Windows Media Player (Windows XP) was decent. Then they made it simpler by breaking everything... Now I need to look for new alternatives.