Wirelessly posted (Mozilla/5.0 (iPhone; U; CPU iPhone OS 4_2_1 like Mac OS X; en-us) AppleWebKit/533.17.9 (KHTML, like Gecko) Version/5.0.2 Mobile/8C148 Safari/6533.18.5)
Depends what you mean by pirated. If it's a free license key and regular install DVD disc, there's no risk other than it might not activate. On the other hand, if you don't have a key and are using a hacked DVD or bootloader, it's basically jailbreaking the OS to bypass the license check and you might not be able to download security updates. Sometimes the pirated windows installers on the Internet intentionally come with viruses installed.
Either way, it's not worth your time. Buy the legal copy.