Comment 2 for bug 156476

DF Marrow, I agree. It is related to another bug I've been looking at:

Bug #108554 "update leaves bootloader unable to find root partition"

In your circumstances I suspect the unexpected "Dell Restore" primary partition *after* the Extended partition is part of the issue. The numbering may have got confused.

Primary Partitions are numbered 1-4. Logical partitions in an Extended Partition are numbered 5-8, so the usual discoery order is:

1 Recovery/Utility
2 Windows
3 Extended
5 Ubuntu
6 Linux Swap

In your case it'll be something like:

1 Utility
2 Windows
3 Extended
5 Ubuntu
6 Linux Swap
4 Restore

The best way to solve it is to use UUIDs to identify each partition. You can discover them using:

$ ls -l /dev/disk/by-uuid

Add them to /boot/grub/menu.lst so you have something like this:

## ## Start Default Options ##

## default kernel options for automagic boot options
# kopt=root=UUID=bb2c3a14-1588-4fb9-8411-71f114b568b4 ro

## default grub root device
# groot=(hd0,4)

## ## End Default Options ##

title Ubuntu Gutsy 64-bit, kernel 2.6.22-14-generic
root (hd0,4)
kernel /vmlinuz-2.6.22-14-generic root=UUID=bb2c3a14-1588-4fb9-8411-71f114b568b4 ro quiet splash
initrd /initrd.img-2.6.22-14-generic
quiet
savedefault

title Ubuntu Gutsy 64-bit, kernel 2.6.22-13-generic (recovery mode)
root (hd0,4)
kernel /vmlinuz-2.6.22-13-generic root=UUID=bb2c3a14-1588-4fb9-8411-71f114b568b4 ro single
initrd /initrd.img-2.6.22-13-generic

title Ubuntu, memtest86+
root (hd0,4)
kernel /memtest86+.bin
quiet

### END DEBIAN AUTOMAGIC KERNELS LIST

# This is a divider, added to separate the menu items below from the Debian
# ones.
title Other operating systems:
root

# This entry automatically added by the Debian installer for a non-linux OS
# on /dev/sda1
title Sony Windows Recovery Tool
root (hd0,0)
makeactive
chainloader +1

# This entry automatically added by the Debian installer for a non-linux OS
# on /dev/sda2
title Windows Vista Home Premium
root (hd0,1)
makeactive
chainloader +1