^^ AMD all the way
though personally I would say do also look for ASUS M2NPV-VM
anyway point is, E2140 with Intel 945 would be under powered
E4400 though is a good procy but I would keep AMD690G or Nvidia 6150 before Intel x3100
@Ron
for software there are different mean, usually every product offer registration so just try the online registration with your product key see if that works out, if it does then you have a Original Software...
For Microsoft Windows, *www.microsoft.com/piracy/howtotell/
Now for hardware what do u mean by duplicate ??