Never check the checkbox to install updates during a Windows 10 upgrade. Let it grab the updates normally after the install.
You don't need to install 7 to install 10 either. You can install 10 1607 via DVD or USB and insert your Windows 7/8 key when prompted. No key needed when your motherboard remembers your 7/8 key in the firmware.
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No need for Pro if you won't use the features. However for a few dollars apart at the locations I posted in the Hot Deals section, feel free to get either.