reinstall windows xp home edition question?

im trying to reinstall windows xp home edition.When i go to set-up a messgae tells me that my \system32\hal.dll is either corrupt or missing and i need to download a copy of that file.Honestly I think somethings wrong with the cd.It seems to be scratched big time.Now,if i get a new cd and reinstall again will everything be alright,would i get all my files back that i need etc.thanks in advance.right now im able to use pc...just cant reinstall using my installation cd...thx again