I bought a copy of Windows Vista when I got a new system in March 2009. In January this year I upgraded to Windows 7 so i've got a copy of Vista doing nothing. Can I give this to someone, will they be able to use it. Not too bothered about selling it, just have a few family members that could use an upgrade to their OS and would be better than it gathering dust. Just want to be sure they could actual use it before I go through the whole process of installing it.