Hah, well, Agent Smith is running a scam here. Nice to see you again Mr. Anderson....
The most important thing to remember is that if you don't enter a lottery, you cannot win, no matter what. It promises you easy money but you'll never see it.
This email comes from a free email server, Virgilio.it, but asks you to reply to an email at Excite.com. This is a sure sign of a scam. The horrible English is also a sure sign of a scam. Forget that it's "Thailand". Thais can speak English as well as anyone else.
It asks for an urgent response but also asks you to keep everything secret. If you won a lottery, wouldn't you normally tell everyone you knew? Of course you would.
It also asks you for a lot of personal information, as all scammers do. And a quick double check of the text at http://www.scamomatic.com/ will confirm that this is a scam.
"If the law can do nothing we must take the risk ourselves...I am not the law but I represent justice..."- Sherlock Holmes