1. Dont forward it.
2. It is spam delete it and instruct the sender that they are an idiot for even thinking it was the real deal
3. Tell them that not everyone wants them to forward the messages to them. It is chain email and annoying
for the low down on the spam.
As for the email. Errr 9/11 was 5 years ago now. So it is perfectly harmless as an email.
With Circa 1,000,000 viruses there are plenty of big threats so emails about potential big ones would be pointless as I cant remember 50 names nevermind 1000s.