Format ubuntu and reinstall

Hello

Note: The following instructions were developed for Windows XP Home Edition.
Other Windows OSs may vary somewhat.

To remove Ubuntu and restore your Windows OS to its original state
System Restore will not work. You must complete three separate
procedures in the following order:

   1. Restore your Master Boot Record (MBR)
   2. Delete the partition
To complete the following instructions you will require two CDs:

* Windows Setup CD
* GParted Live CD. This is the partition management tool I used to
      create these instructions. There are other partition management
      tools available that should also work, but of course the
      instructions will be somewhat different. Instructions for burning
      a copy of the GParted Live CD may be found on the Internet at
      ftp://download.tuxfamily.org/gpartedlive/

and burn the ISO using nero on windows,

More info:

http://asp2.wlv.ac.uk/its/website/selfhelp/help/nero/help_with_nero.asp
(or)
If you are using ubuntu 7.04 or ubuntu 7.10 live CD no need of gparted live CD..

To restore your MBR:

   1. Insert the Windows Setup CD into the CD or DVD tray on your computer.
   2. Restart your computer.
   3. Hit Enter to reboot from the Windows CD when prompted to do so.
   4. Type “R” and hit Enter in Windows Setup to enter the Recovery
      Console. The Recovery Console will appear and list the Windows OSs
      on your machine.
   5. Select the number corresponding to the Windows installation you
      wish to boot into. For most people this will be a “1”. (In some
      versions of the Recovery Console the installations will be
      numbered. In others, you will have to deduce the installation
      number from the order of priority in the list.)
   6. Windows will prompt you for an Administrator password. Try your
      Administrator password or, if your Administrator password does not
      work, hit Enter.
   7. At the Windows prompt, type “fixmbr”.
   8. Type “exit” to restart the computer.

Your computer should restart using the Windows installation you selected.

To delete the Ubuntu partition:

There are several ways you can delete a partition, including Computer
Management (Local) and Command Prompt from within Windows itself (for
more information type “delete partition” in Help and Support in the
Start menu). However, since you will be using the GParted LiveCD anyway,
the following instructions will instruct you in the correct procedure
using the GParted LiveCD. You can go straight from deleting the Ubuntu
partition to resizing the Windows partition. If you have not already
burned a copy of the GParted LiveCD, do so now before continuing below.

   9. Insert the GParted LiveCD in the CD or DVD tray on your PC.
  10. To accept the default boot options hit Enter.
  11. To accept US English language hit Enter.
  12. To accept the default keymap hit Enter.
  13. To accept the default screen depth hit Enter.
  14. Click on the Ubuntu partition in the graphical display.
  15. Press the Delete button.
(or if you are using ubuntu 7.04 or ubuntu 7.10 or 8.04 live cd ..)
Pop in the live cd and go system -> administration -> install and repeat steps 14 and 15

and please post the update manager error here..

Hope that helps

Bhavani Shankar.