Not sure about the fans.
The Virtualization is for emulating an Operating System within an Operating System. Most people dont do this normally or ever in their lives (you dont need to worry about it it wont cause problems). As for the Hyper Threading, it is an old Pentium 4 technology that has been long out dated, plus the Core 2 Duo's wouldnt even have a use for it (no problem there either) .