Here is a guide to the Timeline inside Windows Movie Maker.
Center of Windows Movie Maker
The Timeline is the central area of any video editing program where you actually begin to paste the video together out of pieces. The Timeline ends up being a collection of sequences, either for a small piece of the film or in its entirety. Here all the elements come together, are stacked, arranged, altered, and finished. Windows Movie Maker has simplified the Timeline so that it is easier for novice editors to jump in.
The top, and central, part of the Windows Movie Maker Timeline is the Video segment. This is the top section where you drag and drop specific video clips. Whenever you drop a video clip into there it will automatically position itself either at the beginning or the end of the previous clip, which is much different than most non-linear editing software. In this area you can alter clips, add video effects to specific clips, shorten or lengthen them, or even do specific tool edits.
Associated with this Video track is the primary Audio track. This just contains the audio that associates with the video that is resting in the Video track. This track is also affected by actions that happen in the Video track as they are actually the same piece separated into two different tracks. For example, if you stretch back and shorten a video clip the associated audio track will do the same.
In between the Video and Audio tracks respectively is the Transition track, where you place common video transitions. You find video transitions by looking in the Movie Tasks side bar and selecting Video Transitions under the Edit Movie heading. These then come up in the primary middle window where you can find a graphical representation of the transition. Here you can click them to play a preview of the transition in the Viewer. Then you just drag and drop the transition into the Transition track, but it has to be in between clips, at the beginning of a clip, or at the end of a clip.
Below the Audio track is the Audio/Music track, which is a second audio track. This is intended to be audio that is foreign and not associated with a video clip. These are things like sound effects, soundtrack music, or narration. Windows Movie Maker even has a narration recording tool that then creates an audio track out of it that you import back in and drop it into the Audio/Music track. Essentially you just treat these audio tracks as single files that you put into the Audio/Music track before or after doing any edits. You can also do basic edits, especially as it concerns the length of the audio clip, when it is in the Audio/Music track.
Title Overlay Track
The last primary track is the Title Overlay where you place all text items. These are going to then go over whatever video clip that is standing at the same point in the Timeline. This means that if you want the text to appear on their own then you have to create a blank spot in the Video track where the text is. This is the perfect spot for text cards on clips, titles at the beginning, and credits at the end.