GRUB problem

[Archie]

Yo.
I have accidentally removed the partition that I had my operating system installed on. And bootloader doesn't load my Win7 USB with an error: no such partition. Although I tried to put my HDD last in my boot priority order, it still enters Grub rescue screen. Currently have neither an OS nor a proper bootloader installed on my PC now.

Here some screenies:

[Archie]

Removing GRUB bootloader may be a solution but the problem that is, removing the bootloader is not possible from GRUB Rescue menu as far as I know.

[Huntsman]

Removing GRUB bootloader may be a solution but the problem that is, removing the bootloader is not possible from GRUB Rescue menu as far as I know.

Isnt GRUB like Linux bootloader? Did you dualbot?

[Archie]

Isnt GRUB like Linux bootloader? Did you dualbot?

Yeah, GRUB is Linux bootloader and I did not dualboot. There was only Ubuntu installed on my computer.

Problem solved btw. Booting from CD-ROM did work. But I can't still understand why did that not boot from USB when it was obviously bootable.