Video Thumbnails Maker is a straightforward tool which will quickly create thumbnail preview images of your videos.
The program couldn't be much easier to use. Point it at the individual video or folder of videos you'd like to catalogue (if the file plays in Windows Media Player then it can probably be imported here), click Start, and Video Thumbnails Maker will go to work while you just sit back and watch.
When it's done, you'll find JPG images with the names matching the input videos (so MyMovie.avi will have a matching MyMovie.avi.jpg). And double-clicking any of these will by default show you a 5x4 thumbnail grid of images taken from the movie: in other words, if the clip is 10 minutes long, it'll extract one frame every 30 seconds or so and display the timestamp, so you can see generally what's in a movie just by glancing at the thumbnails.
These default settings don't quite suit your needs? Just click Options. You can set the grid size to vary the number of thumbnails, as well as setting their width and height. You're able to set a time when the thumbnailing begins. You get the option to choose which summary details are displayed about each video (its file name, size, resolution, length and more). And you can control fonts, colours, opacity, backgrounds and a whole lot more.
Please note, while you can use the program for free, donating via PayPal will get you all kinds of benefits: a faster rendering engine, no program splash screen as one of your generated thumbnails, command line interface options and various other extras. Suggested donations range from $10 to $25 and you can read more on the author's site.