This is a quick project I threw together for an assessment. Needed a .NET assembly to take screenshots and have the ability to set an interval and take screenshots for a specified timer, and then zip up all the files and delete the originals. This is a combination of some code from @djhohnstein and @CptJesus's zipstuff.
Screenshot files are saved in the format of <yyyyMMddHHmmss>-<GUID>.jpeg in the directory C:\Users\<username>\AppData\Local\Temp. When using a timer, all the screenshot files will be collected and zipped up into a file named <yyyyMMdd>.zip in the same Temp directory.