+ 6
How trustworthy is the source of what you downloaded? If there's numerous positive feedback, I would feel better about it... but if it's from a random website, I would just immediately delete it, personally.
Could always upload the suspicious file to
VirusTotal, which will have 50+ different virus scanners look at it. Is it just one source saying it's a trojan, or 90%+? That said, I'm particularly paranoid about torrenting/altering video games, so I'd probably be more quick to delete the thing than you are.