help with restoring to factory settings

I just bought a 15' macbook pro from someone and i need to know how to restore it to factory settings and get all of his stuff off of it he didn't have the disk that came with it would i be able to use the disk that came with my 13' macbook on it? or would i need the one for the macbook pro? Also will it ask for a password when i do the restore? Is there a way to bypass it because i dont have the password thanks for your help in advance

No, you need the discs that come with the Mac. The grey discs are particular to the model of Mac that they come with. If you have a black retail disc, you can use that on any Mac.

Thank you so much