I see that there are two new open-source Windows video editors, since I last went looking for a possible replacement for the lumbering heap of annoyances that is Adobe Premiere Elements 12.
Each is relatively simple, compared to the various behemoths that are meant for editing Hollywood movies. They may thus may be useful to you, if the old Windows Movie Maker is too limited or if Adobe Premiere Elements is just too awful an experience to keep on using. I installed both, and as a test I tried slapping together an 28Mb audio .MP3 and a 1Mb still .JPG, and outputing to a video small enough to upload to YouTube (less than 100mb).
* OpenShot 2.0 (beta) has a Windows version and a simple modern interface. Though it’s not 64-bit, which may be why it crashed for me again and again on final rendering, tried with three different export settings. Uninstalled.
* Shotcut. Windows 64-bit, but I never got it to the rendering stage. Because the simple task of fitting a static .JPG onto an .MP3 audio file is made into vastly more work than it should be, and in an interface that only a software developer could really love. Uninstalled.
So, no luck for me with these two. Why are free video-editors such crap? But you may have a different experience. OpenShot 2.0 in particular is worth a try, to see if you get crash-free exports.