Since the Dan Antonielli fix caused AcadLT to hang on startup, I took the BFFI (Brute Force and Ignorance) approach, and tried combinations of Windows 10 settings and AutoCAD settings until I got to a display that is an acceptable compromise across all applications. Not close to perfect, but workable. Here's what worked for me. Disclaimer - I know nothing about this topic, and am not making any recommendations.
In Windows 10, right-click on Desktop, choose Graphics Options / Resolution, set to a resolution near 2000 across, with whatever aspect ratio works best for the particular screen; in my case 2048 x 1152. Set Panel Fit to Maintain Aspect Ratio.
Right-click on Desktop, choose Display settings / Advanced Display settings / Advanced Sizing of Text and other items / Set a Custom Scaling Level (not recommended). Set to 125%. Windows will then make you sign out / in. [FURTHER DISCLAIMER: When you choose Set a Custom Scaling Level, a warning message pops up, describing the burden this setting might place on your computer, and the damage that might cause. Again, I know nothing about this, and I'm not recommending you do it. If anyone has a solid understanding of it, and wants to educate me, please do]
Right-click on the Desktop, choose Display settings. Set "Change the size of text, apps, and other items" to 175%.
Choose Advanced display settings / Advanced sizing of text and other items, and in the Change only the text size dropdowns, set the font size for all six items to 9.
On the Desktop, right-click on the AutoCAD desktop icon, choose Properties / Compatibility, put a check in the box for Disable display scaling on high DPI settings.
Start AutoCAD, and in Options / Display, check Use large buttons for toolbars. The Resize ribbon icons to standard sizes checkbox doesn't seem to do much, if anything. Choose the Fonts button, and set the Command Line Window font to 9 or 10, depending on your eyesight.
The results of all this are shown in the attached screen grabs.
I'm sure I'll get admonished for monkeying around with a bunch of stuff I know nothing about, and I don't disagree. But right now, I have a computer that I can get some useful work out of, so for the moment I'm happy.
Dan