If you have only one operating system i.e Ubuntu is installed on your computer , then it’s very simple because after removing ubuntu you will surely want to install another, you just need to follow this simple steps -
step 1: If you want to install windows after removing Ubuntu, then simply create the bootable disk or USB that you will use for installing Windows 7 or vista (or XP).
step 2: I assume you have already copied (otherwise login to Ubuntu and backup your data) all the data safely to another device or online back up such asDropbox. Next, restart the computer and boot it from the Windows installation disc.
step 3: Now format the ubuntu partition (if you had installed ubuntu on a particular partition) or the harddisk and install windows, follow on screen instructions..and you are Done! That’s All.
2 : Uninstalling Ubuntu from Dual Boot (with Windows 7)
You might be using Ubuntu as adual bootalong with Windows 7. Now, the the next step depends on how you had installed Ubuntu along with Windows 7. The most simple technique is to install Ubuntu using Wubi Installer, which installs Ubuntu on Windows as a program. If that’s the case, then you can uninstall Ubuntu just like any other program from Windows 7 or Vista. It’s quite simple.
On the other hand you might have installed Ubuntu on the other partition in dual boot mode. So now, if you delete or format the ubuntu partition then the windows boot-loaderwill no longer be available because when you installed Ubuntu it has replaced it withGRUB. So you won’t be able to boot into your Windows OS after deleting or formatting the Ubuntu partition.
step 1: Insert the Windows 7/vista/xp DVD and restart your computer.
step 2: Go to recovery windows/console and execute the following command(s) :
bootrec.exe /fixmbr bootrec.exe /fixboot
to overwrite the MBR (Master Boot Record).
step 3: Now, remove the installation disc, restart the computer and format ubuntu partition (ext3/4 file system) to a windows file system such as NTFS or FAT.