Esfour

I have seemed to lost my discs and can't find them. I was going to borrow my friends disc and make a back-up copy so I can use it until hopefully i find mine. I tired using sonic to do a disc to disc using double layer disc. It seems to give me an error message towards the very end of the process. I would like to know if there is a certain program to use or if there is somthing I am doing wrong? Any help would be greatly appreicated. TIA