go down load super grub i keep it handy the grub looks for the menu.1st file and follows it;s instructions. you would think not alway not sure but alot of times I have had to type in the kernel and the hard drive if you installed on a lets say another hard drive and grubb put the boot loader on the hd0,0 =hda1 or= sda1 but you put the install on hd1,0 hdb1 or sdb1 it did not know this default is hd0,0 hda1 sda1.
you need to tell this to grub before you loaded it. I know how are you suposed to knoe down load and burn the super grub do a manual linux load it will find your kernel and load it next time make the boot floppy ok so you do not have this proble boot floppy boot cdrom what ever. good luck my friend here is some examples for diferent hard drive when propted you can edit the comand or type c and then type in a comand.
title linux (hda1)
title linux-220.127.116.11 (hda1)
title linux-2..6.23.12-smp (hda1)
then hard drive 1 partition 2
title Linux (on /dev/hda2)
kernel /boot/vmlinuz root=/dev/hda2 ro vga=normal
# Linux bootable partition config ends
# Linux bootable partition config begins
title Linux (on /dev/hdb1)
kernel /boot/vmlinuz root=/dev/hdb1 ro vga=normal
# Linux bootable partition config ends.
hope this helps.