Am guessing, the op, bought a laptop from pc world, has had some problem with it later on, where by he had to change harddrive.
(And the mistake he made was not making a set of recovery discs
The way round it is if you still have product key on bottom of your laptop, then you could borrow a win7 disc from someone, as you will be using your own key code.
I personally would not accept a copy from anyone, only use a genuine win7 disc.
There will be no doubt a few will pop up and say I have a disc you can borrow, a legit one,,, but when you go collect it, you get told its a copy of a genuine disc.
Stick to genuine, you know what your putting on your laptop then.