What are we supposed to do if we're not sure?

There’s a spot on this site to send malware, and there is a spot to report false positives - but what do we do if we have no idea what we’re looking at on our virus scanner’s results?

it should give you a location for the files, just find it and upload it to www.virustotal.com to double check.

If CIS detects files on your computer, but you’re not sure about them, you can go ahead and report them as false positives here:
Comodo Malware/False-Positive Submission
Comodo will send you an email with the results of their analysis.

If, however, you want to investigate these yourself then please see this guide:
How To Tell If A File Is Malicious

I hope this answered your question.