Rename beep.sys using MS DOS?

my computer gets the BSOD. it says there is a problem with beep.sys. I have a dell, so I used the dell drivers disk (not the Reinstall XP disk). I read you have to rename it to beep.old and replace it. this is all using MS DOS. I know you need to type C:\Windows\System32\drivers then ren boot...etc. however it says bad or missing file, and C looks like C:\>. please help....how do I get to the drivers folder to rename beep.