Not imaginary and not from the tooth fairy. The fact that you believe in
a tooth fairy writes volumes about you, little boy.
Not without a whole lot of work unless the specs of the new computer are
exactly the same as the old one. You'll have to do a repair install that
may or may not work and if, for example, you have XP SP3 installed but
only have an XP SP2 disk, you will also have to slipstream the SP 3 into
XP. Chances are you'll have to do a clean install and reinstall all the
programs, updates and devices.