To Create Windows 7 Repair disk , Get any PC or laptop having Windows 7. On start search menu type "CREATE System REPAIR DISK", select option comes
You will be ask for a Blank DVD, Insert Disk and Burn It, Make a .ISO file with using software named "POWER ISO" In windows 7.
With using Power ISO you will be able to Make bootable pendrive of windows 7 disk by going in TOOLS > Create Bootable USB Or PENDRIVE.
Provide it path of .iso file earlier you created. Now you will be able to run your Pendrive as a repair Disk.
To remove GRUB:
Grab a Windows recovery media or installation CD and boot from it. You should see this on a recovery media.
You should see this on an installation media. Click "Repair your computer" and you
Open the Command Prompt, then type
into the Command Prompt.
Reboot your system now you will be able to load your windows 7.