LuisFERNANDO, welcome to the forum! You state that your pc does not boot. Does your computer power up at all?
If so, you can use your repair disc (or OS disc) to do a repair. Or if you have a recovery partition, you can boot into that (consult your manual for instructions).
Also, a little more info to describe the situation would be very helpful. As much as you can explain would be best, that way you would get more answers.
Best of Luck,
Cat