Hi Michael,
Welcome to Microsoft Community and thank you for your interest in Windows 10.
As per the issue description you are facing issue with fonts which get messed up.
In order to help you better, could you please confirm a couple of things:
I would Suggest you to try these steps if the computer is not connected to a Domain.
In Windows 10, you can now set DPI (Dots per Inch) scaling to make text and other items, such as icons, fonts, and windows, to display larger or smaller for all displays or per-display.
Windows 10 DPI scaling improvements are primarily focused on:
•Optimizing the usability and readability of high-DPI displays
•Providing a uniform experience multi-display systems
•Empowering developers to optimize app-specific scaling based on display DPI
If you are running a screen resolution of 1366x768 on a tablet, chances are that UI will look good at 100% DPI settings. But what about when you connect your system to an external high resolution display? In Windows 8 you can choose either 100% to
optimize the UI on the tablet display or up to 150% to optimize the UI on the external display. You have to compromise.
Windows 10 takes care of this issue by supporting per-display DPI scaling to address. By default, Windows 8.1 will choose the optimum DPI scaling value for each display based on the value chosen for overall scaling in the control panel.
You can change Modern UI text size by following the steps provided below.
•Press Windows key
•Click on Settings.
•Click on System.
•Click on Display.
•Now change the font size according to your choice.
Also refer these Microsoft articles:
Get the best display on your monitor
http://windows.microsoft.com/en-US/windows-8/make-text-screen-larger-smaller/?v=t
Hope this would help. If issue still persists post back with current status of your computer and result of proposed suggestion, we will be happy to assist you.