That's why I hold on to my old computers as well, I never toss a computer no matter how old, that hardware could be very valuable and it's worth holding on to.
I don't like the idea of government having backdoor capabilities and Microsofts closed source makes that difficult to determine what's being done. I know that Microsoft recently claimed that a major crime was thwarted in Canada because of the backdoor which makes me suspicious. Implementing hardware elements wouldn't be difficult either, heck Intel already installed digital rights management into their CPU's and working with hollywood.
I just bought a Sony Vaio FW series laptop and it came preinstalled with Windows 7 and Sony's bloatware, who knows what kind of garbage they installed on here? Granted you don't get the same features with linux, maybe not able to play the newest video games but i'll take security over that any day. Never sell out your security or privacy.