dual operating system problem

if they are on different drives then you have the easiest job ever.

Simply boot to ubuntu and remove the partition that vista is sat on, you will now have unpartitioned space to install XP on. Once installed, You will need to edit /boot/grub/menu.lst to read Windows XP and not Vista (not essential but looks better) but the boot option is identical. The NTLDR (Windows boot loader) will be installed to the drive with windows on it, you are booting to the drive with linux and grub on so this new NTLDR will not affect anything.

Little side not, if you want extra speed you can use a small 2Gb partition on your linux drive, format it NTFS and use it all for swap space. The OS will use the speed of the OS drive but if swap is used then it will start working the other drive too rather than labouring one drive only.

HI :)

At your boot-menu do you have just 1 choice for Windows and just 1 for Ubuntu or do you have lots of choices for Ubuntu?

Lots of us keep a working Windows partly because installing Windows is such a nightmare. Since you already have Vista working then i would recommend keeping that as the Windows on you system. Some people also install a Windows inside a virtual machine inside Ubuntu and although they often do that using the same Windows as the on in their dual-boot that might be a better place for your Xp.

Also please can you get to a command-line and give us the result of

sudo fdisk -l

where " -l" is a lower-case " -L"
https://help.ubuntu.com/community/UsingTheTerminal

Good luck and regards from
Tom :)

ActionParsnip's answer works as long as you haven't installed Ubuntu using the Wubi. Unfortunately it's quite likely that you have.

Good luck and regards from
Tom :)

ANIRUDDHA,
"using Wubi" means you installed Ubuntu from within Windows.

Tom, if you install Ubuntu by Wubi and choose ANOTHER drive isn't GRUB placed on that another drive, separated from Windows?

actionparsnip,
if I place my Linux swap space would it gain speed if I run a few light applications? And - the same - if I run more and heavier apps?
I'm sorry for my offtop.

Swap space needs to be between Ram and twice ram size. If you have it on a separate drive from the Ubuntu OS & programs then you might well notice quite an improvement in performance. Note the read/write speed is significantly faster at the front of a drive (unless it's an SSD one) so if your swap is being used a lot then having it near the front of the drive helps a lot too. Generally your swap will be used a lot if your ram size is under 2Gb or if you run a lot of very heavy apps such as heavy games, high-def movies, virtual machines and stuff like that. So if you only run a few light apps then you might only notice an improvement if you have something like 512Mb ram.

Yes if you know a fair bit about linux then it's fairly obvious whether you have installed Ubuntu inside Windows or on a separate partition. Remember that Windows tends to call a second partition on a drive another drive - typically "C: 'drive'" and "D: 'drive'" will both just partitions be on the same physical drive. Also when you run the Wubi it's setup to make you think it's on a separate drive when it's really just inside a Windows partition. This all helps to make it easier for people trying out linux for the first time!!

Luckily you can tell if your running a Wubi or a full dual-boot by looking at how many options there are for booting it Ubuntu at the boot-menu. The full install has lots of options and a "memtest" and allsorts. The Wubi gives just 1 option for each OS.

Hopefully this hasn't scared you off! Please let us know about your boot-menu and we can help you from there!
Good luck and regards from
Tom :)

dear actionparsnip,
               how can i edit /boot/grub/menu.lst? i mean ,i need exactly the command i have to type on terminal .please.....

and dear Tom,
      at boot-menu a number of choices appear for ubuntu.
      the command sudo fdisk -l results....
                      Disk /dev/sda: 80.0 GB, 80026361856 bytes
                      240 heads, 63 sectors/track, 10337 cylinders
                      Units = cylinders of 15120 * 512 = 7741440 bytes
                      Disk identifier: 0x31a431a3

   Device Boot Start End Blocks Id System
/dev/sda1 * 1 2709 20472832 7 HPFS/NTFS
/dev/sda2 2709 10336 57665317+ f W95 Ext'd (LBA)
/dev/sda5 2710 5418 20480008+ 7 HPFS/NTFS
/dev/sda6 5419 7856 18431248+ 7 HPFS/NTFS
/dev/sda7 9103 10336 9321472 7 HPFS/NTFS
/dev/sda8 7857 9103 9422091 83 Linux

   thats all...................

Hi :)

It does look as though you have installed Ubuntu on a separate partition, not inside Windows :)

It also looks as though you have a lot of different partitions for Windows. Did you used to have Xp on this machine? When you are in Vista do you see a lot of other 'drives'? Vista should see 4 'drives'.

In Ubuntu on the "Places" menu it should be showing a menu item "Removable media" with 5 'Media'. These may all be full of data you want to keep and it's unclear exactly which one has Vista on it. Note that deleting the Vista partition will also delete the data on that partition so it is probably worth moving all the data off the Vista partition first, or at least everything in the "Document & Settings" folder, perhaps a few other places too - Windows tends to scatter pictures from cameras and stuff like that although mostly it just scatters into odd places in the "Documents & Settings" folder that contains all the 'users' on your system.

Please could you get to a command-line
https://help.ubuntu.com/community/UsingTheTerminal
and type in

cd /boot/grub
ls
sudo cp menu.lst menu.lst.100809
ls
gedit menu.lst

Note that "ls" is a lower-case "LS" and should give a LiSt of what's in the folder. The "sudo" command will ask you to type in your normal user password, not your SuperUser/Root one but does give the command SuperUser/Root privileges. The"cp" command should create a copy of the "menu.lst" (a lower-case "MENU.LST") and give it the name "menu.lst.100809" so that we know what date this backup was made. The 2nd "ls" should show that the new file is in the folder :) The text-editor called gedit should show the menu.lst which would be great to copy into here.

Good luck and regards from
Tom :)

Hi again, sorry i have lost track a bit. Do you have an ubuntu cd and have you managed to boot up from it into a LiveCd session via the "Try Ubutnu without making changes to this machine" option in the cds boot menu?
Regards from
Tom :)

According to your output you only have a single disk with NTFS and EXT3 on which is contrary to your 2 disk setup you initially stated.

You will need to reinstall GRUB once you install XP as XP will overwrite the boot sector with NTLDR which is a real pain to get to oot Linux (but it can). Grub is much more flexible (and GRUB2 & LILO is more flexible still) and can boot both.

If you follow this guide to reinstall Grub it will work out fine for you:
https://help.ubuntu.com/community/GrubHowto

Yes, i thought this was likely. It's the Windows way of trying to confuse the issues which is why we asked for the output of "sudo fdisk -l". It's not your fault, it's microsquish's fault.

https://help.ubuntu.com/community/WindowsDualBoot#Recovering%20GRUB%20after%20reinstalling%20Windows
As you will see from the guides this is only going to be possible if you have a linux cd, any will do but Ubuntu is easier because it's more familiar. If you have not got an Ubuntu cd then please get either sliTaz (30Mb) or Wolvix Hunter 1.1.0 (450Mb)
http://distrowatch.com/table.php?distribution=slitaz
http://distrowatch.com/table.php?distribution=wolvix
just follow the link to the download mirror and when you get an iso make it into a cd the same as you would for Ubuntu
https://help.ubuntu.com/community/BurningIsoHowto
I tend to find the cheapest cd that can only be bought in packs of 10 or more are better than more expensive ones which can be bought singly, but any cd is better than dvd for this purpose.

I would be really tempted to leave Vista as it is, move all your personal data from the other partitions onto one partition and then delete the empty ones to make room for a new install of Xp. Quite a lot of people have a multi-boot. My neighbour has one machine with Xp, Vista, Win7 and LinuxMint on it. <shrugs>

Anyway, to do this you are going to need a linux cd that allows you to get to a command-line so that you can call up grub and fix the Master Boot Record to point at grub - then we will need to edit grub (GRand Unified Boot-loader) to include Xp. It's not really too bad. It is possible to edit NtLdr but i haven't a clue how to do so and even my neighbour had troubles doing so. You will have seen the grub's menu.lst is just a text-file that can be edited (although i asked you to open it "read only" just in case you accidentally made a mistake and saved it.)

If you do copy the menu.lst into here then we could work out which of your partitions has Vista on it and that would help us work out what to do when you decide whether you really want to delete Vista, or just add Xp to make a triple/multi-boot - or whether to just tidy up your partitions to give Ubuntu more room so you can install Xp inside a virtual machine inside Ubuntu :) It would also help us to help you get your personal data safely off whichever partition Xp is going to be installed on.

So, please let us know if you have a linux cd and also lease copy&paste your menu.lst into here so we can help you.
Good luck and regards from
Tom :)