If you accidentally deleted important files on your system, there's no way to ``undelete'' them. However, you can copy the relevant files from the floppy to your hard drive. For example, if you deleted /bin/login on your system (which allows you to login), simply boot the boot/root floppy, mount the root filesystem on /mnt, and use the command
The -a option tells cp to preserve the permissions on the file(s) being copied.
Of course, if the files you deleted weren't essential system files which have counterparts on the boot/root floppy, you're out of luck. If you made backups, you can always restore from them.