I can't boot windows xp after installing ubuntu 10.04!!!
 

I tried deleting the partition where ubuntu was installed using the boot cd and going into its demo mode of ubuntu. I thought this would delete Grub but i was wrong so now grub cant find the partition ..I would like to believe if I were to delete grub off the system I could boot windows xp.
what should I do?

I'm not quite clear what you're asking. Are you saying you ONLY want XP? If so:

No, you need to reinstall Windows' bootloader. If you have no bootloader of course you can't boot anything; it's not magically replaced.

Boot your XP CD into Repair mode. Enter "fixboot" then "fixmbr". You should be able to boot XP (and nothing else).

thanks a lot and yeah I do now only want xp. Also if I want to install ubuntu again what can i do to dual boot sucessfully and not have this problem reoccur?

Usually all you have to do is install Ubuntu and it will detect both Windows and Linux. Just don't delete it if you want it.

if you don't want to deal with such problems later , better you install your distro in Sun Virtual Box.

http://www.virtualbox.org/wiki/Downloads

it will virtually install the guest os in your windows system.

And I ve not came to know any its limitation so far!!
I believe it prefect, and using 13 virtual OSs on it for last 3 years !!