First thing to do is boot. you should locate the grub.conf file with the find command.
This will print out a partition in form of (hd0,0) or so.
Then just run root (hd0,0) (depending on what the result was, make changes.
This should all go without errors.
then run kernel /kernel (press TAB to get options)
kernel /boot/kernel (press TAB to get the options)
initrd /initrd (press TAB)
initrd /boot/initrd (press TAB)
The right ones are the ones, that do not produce errors.
Once you have run all these without errors (might take some changing from you) Just experiment, you cant mess anything.
Press TAB a lot of times after every command you type, to give you more options.
Ok, so let's say you got through without errors. Just type boot and press ENTER and away you go to Linux.
Once in linux. login as root and let us know
Try to post your fdisk -l results and /boot/grub/grub.conf file contents.