My desktop doesn't BOOT

You may have messed up your Master Boot Record.

What is the error you get?

You should be able to boot off a CD if you set your BIOS correctly.

Hope this helps,
Michael

I uninstalled ubuntu from my desktop and also the partitions. Now my machine doesn't boot and shows a command prompt saying something about the grub loader. I tried booting from a windows cd but didn't work. Anyone who has faced such probem earlier or knows a workaround for it then, please answer to this question.

Error message shown is: GNU Grub Version 0.97 (572K lower/1028944)
[Minimal BASH - Like line editing is supported. For the first word, TAB lists possible command completions. Anywhere else TAB lists possible completions at a device/filename.]

grub>_

I deleted fedora partition on windows from my desktop. Now my machine doesn't boot and shows a command prompt saying something about the grub loader. I tried booting from a windows cd but didn't work. Anyone who has faced such probem earlier or knows a workaround for it then, please answer to this question.

Error message shown is: GNU Grub Version 0.97 (572K lower/1028944)
[Minimal BASH - Like line editing is supported. For the first word, TAB lists possible command completions. Anywhere else TAB lists possible completions at a device/filename.]

grub>_

Hm, You should be able yo restore your MBR with that windows CD, so you need to access your BIOS.
When your computer is booting, before it gets to the GRUB screen, try hitting any of the following keys:
F1, F8-F12, Delete
One of these keys may bring up a screen to allow you to choose what medium to boot from, this is not what you want.
You should get either a blue or black screen to come up; and there should be a tab called "boot" or under one of the topics should be boot order or something like that. Once at that area, make sure that CD drive is on the top.
Reboot with the cd in the drive, and it should work.

HTH
Michael

when i try to boot windows from the bootable windows cd the screen goes blank

when i try to boot windows from the bootable windows cd the screen goes blank

Just blank? Or is there a blinking underscore in any of the corners?

You cd may be scratched, try putting it in a computer thats on and see if it gives the cd a name like "WINDOWS_BOOT"

The blank screen doesn't have any blinking in any of the corners of the screen. Also the CD that I have been trying to boot from is in perfect condition, I even tested it in a different machine.

Are you sure the CD drive is OK?