3. Rename it to whatever.com . You shouldn't even have to run it - changing the name of the file should be enough to activate your AV - but running (opening) it is harmless and should generate the same warning.
Just about an good av should detect it, and I highly recommend trying the EICAR test. It's good to try when switching to a new anti-virus, anti-trojan, anti-spyware product just so that one can get used to it's dialogs for dealing with a test virus, versus waiting for the real thing.
Yeah, it an standard test file that all antivirus software detect, so that people can verify that their software is correctly installed and configured and works.