I have a dell inspiron. I have a dell inspiron 6400. was working fine I shut it down and the next

Question

I have a dell inspiron 6400. was working fine I shut it down and the next day tried to start. got an error message windows will not start. Missing or corrupt \windows\system32\config\system. Daughter can not find original Windows CD. I have a Dell Latutude D830. Tried my CD of Windows to re-install XP. XP installed but now the wireless doesn't work. Not sure how to get it working. Please help!! need to download new drivers.