This may or may not seem like a silly question to a lot of you...  Recently my office has needed a video which is already on YouTube to be posted on our web site.  Under normal circumstances, we would just embed it, but, as it happens, this particular one is an hour long and we only need the last 30 minutes or so.  We would like to download it and edit it, but in looking into this, I was presented with the option of downloading free converter software.  Rather than submit my diocesan computer to potential ravishing of malware via unfamiliar and untrustworthy software, I thought I might ask if anyone out there has a solution.

Is there a free converter that you all trust?  Or perhaps should I be going about this in a different manner?  I will appreciate the input!