Well, I flashed the BIOS and decided to run the installation one more time. This time I did expert mode. I partitioned the hardrive and installed all the nessessary software to boot and run Linux (includiong the bootloader LILO). I even created a boot floppy. Unfortionately, when I rebooted, the same message ("missing Operating system") appeared. I decided to try the boot floppy. I rebooted with the floppy in the drive. It started to boot off of the floppy, got past the delay, and then gave me a message that said "Boot Failed". I'm pretty sure it's official that Mandrake Linux will not work on this machine. I'm not that upset because this was not a machine that I had any intentions of keeping. This was just to experiment on. I just hope that the computer which I DO plan to keep will load Linux.
Thanx for everyone's help and patience!