I can't seem to figure out what the entry should look like in the Menu.lst file. I have an old PC where the CD doesn't boot or USB. Tried installing Grub on a 3 1/2 inch Floppy, but whatever I put doesn't seem to work. when I'm in the Grub Menu and type find /vmlinuz I get entries form my hard drive, but no entries at all for the USB I have plugged in. Is there a way for Grub on the 3 1/2 Floppy to recognize the USB I have plugged in with its various partitions? I didn't know where to post this, figured I'd try here.
***Purpose for doing this is I want to use an old pc to boot Grub from a 3 1/2 Floppy and use a USB stick as storage for the PC. I don't want to use a hard drive (i.e. a very quiet pc).
Any help would be appreciated.

I think you are SoL (sh*t outa luck).
I expect grub to only talk to devices it can "probe" the BIOS for - i.e. bootable devices. Been too long since I've seen such a beast to be really sure I must admit.
Once you get a kernel booted (with usbfs active), you could chroot into the USB environment. May suit what you want - or not.