Posted 01 August 2006 - 01:14 AM
While I've never heard of this method, or anything similar to it, being used in this manner, I would guess that it would protect you against the lesser quality viruses, but that rootkits and really nasty viruses may be able to bypass it. Perhaps one of the more experienced members will be able to answer you more definitively.
In any event, be sure to keep your antivirus, antispyware, firewall, and Windows itself up to date, and run the scanners regularly.
It should be noted that running two copies of Windows without buying two product keys may be a violation of your EULA, even if it's on the same computer.