Using the Recovery partition should put the computer back to factory state. Apparently it doesn't effect the master boot record?
So you still have the mbr part of Grub looking for the Ubuntu partition you have overwritten with your windows Recovery. You can overwrite Grub in the mbr from the Ubuntu USB by opening a terminal and typing the command below. This will delete Grub from the mbr but obviously won't put any windows code there. You will need a windows CD to do that. I don't think a Recovery CD will do and you will likely need the full installation CD/DVD. If you don't have the installation CD, you can purchase them for a minimal cost if you bought the laptop from a major wholesaler. You could also just reinstall Ubuntu on a small partition and just use its bootloader or you could install another smaller distribution of Linux to use its bootloader. NOTE: The code below will only work if you have only one hard drive. Do not have any other hard drives attached. If you are not sure run sudo fdisk -l(lower case Letter L in the command) first and you could post that here. And obviously, your computer will be unbootable after but it is now. You should of course, still be able to boot from the usb/flash if your computer has that capability.
sudo dd if=/dev/zero of=/dev/sda bs=446 count=1
I would think you could borrow an installation CD for win 7 from someone and use it to restore the bootloader. Since this is basically a windows problem, you might try some windows forum also.