The quick way I have as a 'heads up' when I think something might be a Hoax is to cut a section of the email ( 7 or 8 words, so it's long enough) and paste them into a web search engine ( I like Every Click )
How do you recognise if it's a Hoax? Well I've started to get a 'sense' for it. This is partly through trusting my intuition also reading about it. There is some really good information about how to recognise Hoaxes at http://www.hoax-slayer.com/#latest-email-hoaxes
I find this http://www.hoax-slayer.com/ website generally is also a good way to check if something is a Hoax
It's also useful to know and use some basic email saftey measures.