[ubuntu] Uninstalling ubuntu

You don't "uninstall" operating systems which is what Ubuntu is. That is only for software applications installed within an operating system. What you do is to format the partition. Before formatting the partition, if you have another operating system on the computer, you need to make sure that you can boot it (windows) without using anything from the other system (Ubuntu). The reason for this is that there is minimal boot code in the MBR and the rest of the boot code/files are on the partition. So if you were booting both Ubuntu and windows with Grub, you deleted the boot files without setting the system to boot from windows first.

You can clearly see this in the boot repair output which shows Grub code in the MBR looking for its files on sda5 (msdos5) which clearly does not exist.

The error you got on trying to update-grub is because you ran it from the DVD which won't work. Actually, you don't have the necessary Grub files so there really isn't any point in trying to reinstall it as you would need to create a partition for it. You don't want to install it on a windows partition as that will mess up the windows boot files also. You could reinstall Grub but you would need somewhere to put it and you only have windows partitions.

The standard method of repairing this is to use the repair option on your windows installation DVD. See post three at the link below for the commands you need to use. If you don't have a windows installation DVD you will have to do an online search for some software to use to repair it. I've read that Hiren's boot CD will work but haven't used it myself.