Para a inicialização do Windows, vá pela BIOS de sequência - > MBR (Master Boot Record no HDD) - > Registro de inicialização de partição - > BCD - > OS
O GRUB geralmente é instalado no MBR ou na inicialização da partição, portanto, você pode restaurar o MBR e o registro de inicialização da partição para eliminar o GRUB e restaurar a inicialização do Windows.
Tente este procedimento para restaurar ( link )
Se você já tentou "bootrec / FixBoot" certifique-se de fazer "bootrec / FixMbr"
Boot from the original installation DVD (or the recovery USB)
At the Welcome screen, click Repair your computer
Windows 8 Repair Your Computer Menu
Choose Troubleshoot
Choose Command Prompt
When the Command Prompt loads, type the following commands:
bootrec /FixMbr
bootrec /FixBoot
bootrec /ScanOs
bootrec /RebuildBcd
Press Enter after each command and wait for each operation to finish
Remove the DVD from the disk tray
Type exit
Hit Enter
Restart your computer and check if Windows 8/8.1 can now boot
If bootrec utility doesn’t fix your Windows 8/8.1, try following the next commands to fix the EFI bootloader of the Windows 8/8.1:
Boot from the installation DVD or the Windows 8 or Windows 8.1 recovery USB
Click Repair your computer
Choose Troubleshoot
Choose Command Prompt
Type these commands in order and hit Enter after each:
diskpart
sel disk 0
list vol
These commands will select the first disk of your computer and the list all the partitions available on that disk.
Check for the volume item that has the Fs column FAT32. The EFI partition must be formatted under FAT32.
If the volume number of EFI partition is “2”, type the following command:
sel vol 2
If the volume number is different than 2, replace “2” with the number available on your computer.
Assign a letter to this partition, a letter that is different that those already available on your computer, for example x:\. Type this command to assign the letter:
assign letter=x:
Wait for the success message to appear:
DiskPart successfully assigned the drive letter or mount point.
Type exit to quit the DiskPart utility:
exit
Type this command and replace x:\ with the letter you assigned earlier to the EFI partition:
cd /d x:\EFI\Microsoft\Boot\
Then type the bootrec command to repair the volume:
bootrec /fixboot
Now you need to backup the old BCD and recreate a new one. Type:
ren BCD BCD.backup
Type this command to recreate the BCD and replace the x:\ with the assigned letter earlier:
bcdboot c:\Windows /l en-us /s x: /f ALL
In above command, Windows is installed on c:\. If the drive letter where your Windows 8/8.1 is installed is different, replace c:\ with your drive letter.
Remove the DVD from the disk tray
Type exit
Restart your computer
"bootrec / FixMbr" e "bootrec / FixBoot" definitivamente substituem os registros de inicialização do GRUB pelo Windows e o suficiente para ganhar 7 ou mais, mas eu não tenho muita experiência com o EFI.
Upd.
Eu olho para o seu botinfo. Parece que não há partição do windows, ntfs ou FAT32 no HDD (sda). Você instalou o Kali no disco rígido e o formatou.