How do i get back into my (Win95) OS?

I recently got a used computer on which the cdrom wasn’t working. I moved the jumpers, and when i rebooted, got an error msg: “invalid startup disk”. I am now using a boot disk, as well as a win95 cd, and i can only get to the A prompt. Has the os system crashed, or is there another way to get to it? There’s some info on the hd i’d like to retrieve, so i don’t actually want to reinstall the os just yet, but i will if i have to. Pls help.