When you download video from your camera to your computer, Windows Movie Maker by default will split longer video into shorter clips. These clips were created when you stopped or paused recording with your camera.
If you notice that Movie Maker did not automatically split your video into clips, you can turn this option on, and then trim your video clips to show the most important moments.
Under Capture Video, click Import Video.
On the Import File dialog box, select the Create clips for video files check box.
Click your video file, and then click Import.
In the Collection pane, right-click the video, and then click Create Clips.
Drag clips from your collection to the storyboard at the bottom of the window.
Select the clip you want to trim, and then, in the Preview Monitor, click the Play button.
Play the clip until it gets to where you want to trim it, then click the Split Clip button. This cuts your clip into two separate clips that are added to your storyboard.
Delete the portion of the clip you don't want by right-clicking it, and then clicking Delete. Repeat for each clip. You can split clips several times to use more than one moment from a clip.
If you do a lot of editing, you might want to use the timeline view, which shows you how long each clip will play. Click the Show Timeline button on your storyboard.
Windows Live Movie Maker 2011 offers faster and simpler ways to turn your photos and videos into polished movies, with more capability to share your creations with your friends and family. To get Windows Live Movie Maker—part of the Windows Live Essentials suite of products—simply upgrade to Windows 7.