OpenShot is a fantastic video editor for Linux. It can handle almost all the operations you might want to perform to create a simple video.
Features I relied in it include:
Content can be laid on two tracks. For example, a background color and text on one and a small video in another. These will be automatically combined for the final video.
Slides of text can be added. This is useful to add title pages. These can be edited in OpenShot or for more complex editing, it opens it in Inkscape. This is all possible since these are just SVG files.
Images and image sequences can be added. Inter-image transition times can be set easily.
Easy to create videos for various modern output venues like YouTube.
One terrifying simple feature that is missing is that you cannot add content to the beginning or middle of the track by shifting stuff over to the left or the right! Users have discussed it over here, but do not expect the feature anytime in the future.
Tried with: OpenShot 1.4.3 and Ubuntu 14.04