Is MalwareByte trustworthy?
I'm thinking of a serie episode I saw on blackmirror where the guy got a much more worst malware by trying to get ride of a malware
Yes, MalwareBytes is trustworthy and is a good free option for scanning your PC.
Eset's NOD32 is also a great antivirus product if you are willing to spend some money.
Some other free options include:
Trend Micro House Call:
http://housecall.trendmicro.com/SpyBot:
http://www.safer-networking.org/index2.html