I am looking for a screen-recordings software that will work on Windows 7 and will not require installation. Free software is my preference and I am fine with advertisements as long as there are no watermarks. Basic functionality of recording the desktop in common media format such as WMV, MP4, MOV will suffice and advanced functionality is not required. I used OBS before, but that requires installation.
ShareX would be a good option. It is a general screenshot tool but also provides very good Screen Recording functionality.
You can download the portable version from their official Github page here (file would be ShareX-portable.zip)