When attempting to use the diskette I received the error message "the second stage of the install which you have selected does not match the boot disk which you are using".
The client's current configuration includes software raid. Is this message created possibly because I am trying to use this diskette to install on a system that has a single hard disk?
No, it's because the version of the CDROM you are using does not match the installed version, or at least, the version which supplied the "reinstall floppy" feature. It's possible that the installed version does not include the "reinstall floppy" feature (it was dropped, because boot kernels became too large to fit on a floppy - I don't remember in which version), but your system was upgraded from an earlier version. If that is the case, then the "reinstall floppy" will still appear in the menu, but won't be useful.