Helpppp

Hi, I am new to the forum, but not completely new to linux. I seemed to have caused myself all sorts of issues at the moment. Background for my problem: I recently got a new hard drive, put it in my computer and put a fresh install of linux mint on it. Everything is going great, I managed to get almost all of the software I need for college to run. Except....one thing. It will work, but I need the whole license numbers and such and can't get that until Friday. I have my old hard drive, with windows 7 still installed in a mount that allows me to hook it up to my computer via usb (the front got damaged and it will not go directly back into the computer). I seemed to have killed whatever boot loader is used for the windows because when I try to boot from the usb hard drive I get an error saying that grub isn't there. I believe this is from when I installed ubuntu on a flash drive while that old, windows, hard drive was still in my computer and put grub somewhere that turned out to be a poor choice. Basically what I need to know is if there is a way to get my windows, on the external hard drive, to boot so I can go on and use an application I need for class. I don't care how its done and after Friday won't ever need it again. I have searched and searched for a way to do this without the install CD (computer came with it from my college) and have not found anything useful. Any help would be greatly appreciated. BTW I currently have a flash drive available to me to install some type or rescue distro but I do not have any blank CDs.

Moved to Other OS/Distro Talk forum.

Can you disconnet the Mint drive By unplugging the wires to the power and the ribbon or sata cable? then set the bios to start off of the usb where windows is?