Is the CD you copied from your friend a CD containing SP2 for Windows XP or is it a Windows XP installation CD with SP2 integrated? Please clarify... In the second case, we are dealing with piracy... so discussion on that is not allowed... If you got a Service Pack CD copy, it is possible the CD did not burn properly, so try to get the original and try to install with it...
BTW, could you post the detailed error message... Is the missing file name mentioned?
Arun