I have a system with both a WinVista install (for my girls Sims and wife's itunes) and LM 9.

I attempted to create a new partition for a dedicated /home partition to make upgrading in the future easier.

I think by deleting the first partition (an OE Recovery partition) and moving things around, I messed up my MBR or Grub2 file, because I can't boot either O/S.

Output of fdisk:

Disk /dev/sda: 320.1 GB, 320072933376 bytes
255 heads, 63 sectors/track, 38913 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x81f5ee4e

Device Boot Start End Blocks Id System
/dev/sda1 1 674 5413873+ 83 Linux
/dev/sda2 * 675 12650 96197220 7 HPFS/NTFS
/dev/sda3 12687 38914 210663425 5 Extended
/dev/sda5 12687 20293 61096066+ 83 Linux
/dev/sda6 20294 38131 143283703+ 83 Linux
/dev/sda7 38132 38914 6282240 82 Linux swap


sda1 is empty
sda2 is windows
sda 5 is LM9
sda6 is going to be new home partition


I also have a LM9 live cd ready to go.

Also, after trying:
sudo mount /dev/sda5 /mnt
sudo mount -o bind /sys /mnt/sys
sudo mount -o bind /proc /mnt/proc
sudo mount -o bind /dev /mnt/dev
sudo chroot /mnt
grub-install /dev/sda
update-grub

On boot, I get an error msg after a grub screen with only linux as an option saying:
the disk drive at /mnt/sda7 is not ready or not present.

Also -

tried to install grub using:

mint@mint ~ $ sudo mount /dev/sda5 /mnt
mint@mint ~ $ sudo grub-install --root-directory=/mnt/ /dev/sda
grub-probe: error: cannot find a device for /boot (is /dev mounted?).

I think "cannot find a device for /boot is one part of the problem....

I can get Linux to partially boot when I install grub from a LiveCD, but I get the "the disk drive /dev/sda7 is not ready or not present. Press s to skip or M for manual mounting" error msg. After picking either option, System just hangs.

And sudo update-grub:
Generating grub.cfg ...
Found linux image: /boot/vmlinuz-2.6.32-21-generic
Found initrd image: /boot/initrd.img-2.6.32-21-generic
ls: cannot access /var/lib/os-prober/mount/boot
Boot: No such file or directory

You need to make sure your Grub is on the partition you think it is since you deleted and recreated a partition. Use the Live CD of Mint, open a terminal and get to a grub prompt by typing: sudo grub
Then type find /boot/vmlinuz and check the results.

I'd suggest creating a mount point other than the /mnt directory for Mint. As root, sudo mkdir /mnt/mint, then mount it as root:
sudo mount -t ext4 /dev/sda5 /mnt/mint

See if you can browse your Mint files. Particular attention to the /boot/grub/grub.cfg file which should contain your menu. See if it pointing to the correct partition.

I have not used Grub2 so can only point you to this tutorial for info:

http://www.dedoimedo.com/computers/grub-2.html

Sadly, it looks like I have grub2 installed rather than grub, so I can't execute your first command