Surprisingly, YouTube itself is a source. Using the on desktop, you can legally download your own uploaded content. However, for movie clips, you must use the "Creative Commons" filter. Search for "2012 movie review" or "2012 scene analysis" and filter by "Creative Commons." These clips are often short snippets uploaded by educators for reuse.
When you search for "download movie clip 2012," you will encounter a minefield of websites. It is vital to distinguish between legal fair use and copyright infringement. download movie clip 2012