I want to have 2 totally different computers in one pc. I would like this to happen maybe with dual boot? I dont want the files from the one HDD to be accessible to the other because the one HDD might have corrupted files (viruses (false positives etc inside). Please tell me a way in how I can have those 2 HDDs as different computers under the same pc box but to not be linked together. Both HDDs will be running Windows OS (XP or win7) but on both the same OS.
(Please dont tell me to remove the viruses from the one HDD they are there for a reason its false positives)
Thank you for your help and time!
I would personally attempt this:
Get the operating systems to dual boot XP in the first place. Get your boot menu to work, and then boot one of the operating systems. From there, encrypt the entire disk that this system is on. This will make it inaccesible to the other.
On the other disk, do the same exact thing. They might appear in Disk Management / My Computer, but they will be encrypted, therefore non-accesible.
There is no way I know of to restrict your operating system to access all the components connected to your computer. Of course you can dual-boot between different operating systems, even if they are the same - say 2x win7 - but the one OS will still have - at least basic - access to the other drive. (if you take security measurements, the malware has to be pretty advanced to access the other drive though, most malware will not be able to do so, but it is still not impossible)
If you want to seperate the physical hardware layer from the logical layer your operating system provides to your applications (and malware) you would have to put a layer in between the operating system and the hardware. The only solution I see here is to run a virtual machine.
The other solution would be to physically change the harddrives, there are several solutions available that support changing drives via front panels.
But, there is malware that can write itself to the boot sector or even to the BIOS' flash, against those baddies changing drives or encrypting them (as recommended by ekaj) will not help. An encrypted drive aditionally only makes the files on it unreadable, but the drive can still be accessed by the malware and get corrupted. I still highly recommend a virtual machine, although there is malware out that is able to escape such secure enviroments.
This question is very old, but I thought I would provide an answer anyway.
The easiest way to do this would be using using hard drive bays like this. Buy two and install the drives into them and install them into your computer. You will see from the features listed in the description, it has a key based power lock. Those locks provide power, meaning if the drive is unlocked it will not receive power and cannot be used. So by locking and unlocking drives as needed, only the drives you want will be usable.
There is a number of ways you could do this.
Removable hard drive trays - plug the drive you want at this moment in. Theoretically you could do this with an external hard drive dock.
Virtualize. Setup both operating systems as separate virtual drives under a main OS. Start only the virtual drive you want. Either that or use a bare-metal hypervisor where the hypervisor starts up and then select whichever drive to load.
Encrypt - setup the separate drives as different encrypted drives. Upon boot, tell the bootloader which drive to start. Do not automount the other drive. Not sure if Truecrypt could do this or not.