You should be able to switch users by choosing that option from the Start square then Power. It really is no different from the way it was from way back. If you really want to revert and you only had the upgrade within the last month. Go to Control Panel and you'll find an icon to do that for you.
That said, many of us believe Windows 10 will be the only version left standing after Vista, 7 and 8 and killed off and the 10 will be quietly dropped in faviour of just plain Windows. The rest will just be updates and Sevice Packs from then on.
There is third party software to make 10 look just like 7 if that would help you and your husband. What difficulties does he have?