Hi Jack,
The font will go the C:\Users\Username\AppData\Local\Microsoft\Windows\Fonts if you select only the install option. While the install for all user options will go to the default c:\windows\fonts directory.
You might be receiving an error deleting the fonts because it is still in use by the system. Open the registry editor then navigate to this location "HKEY_CURRENT_USER\Software\Microsoft\Windows NT\CurrentVersion\Fonts"
Delete all the instances there then reboot the PC. Once logged in you can then delete the fonts in the C:\Users\Username\AppData\Local\Microsoft\Windows\Fonts.
Best regards,
Van