yes, virus can move but if you set up a good firewall and update your antivirus religously,and set password access to all partitions; set the partition property for not sharing, archive and read only.. the chance you will get infected are small to none.. virus writer doesnot care about spare storages and second HD, the ultimate prank is to attack the operating system which is the most vulerable, to encode a subroutine to destroy a second partition require too much space have to get to root directory which will cause time to download and easy to detect.. back up in DVD+/-rw and set your recovery console..you will be just fine... Donot sweat the small thing, go backup...

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