Karen:
I tried the steps you suggested, including doing them after a clean install, and it didn't seem to fix the issue of being able to select and type values into various dialogue boxes (e.g. the "Analyze / Multi-Aperture..." dialogue.) However, I CAN change values via the sliders in the Multi-Aperture dialogue (as I could before trying your suggestion).
There seems to some conversations on-line about ImageJ not running well on MacOS 10.13 in general - including missing the menu of commands (one of my students ran into the missing menu issue - I didn't, but did experience the typing-in-dialogue issue).
http://forum.imagej.net/t/fiji-or-imagej-lost-menu-in-new-macos-high-sierra/6222/6Luckily, Fiji seems to work fine on both of our laptops....
And to clarify, I'm on 2016 MacBook Pro 13" with the touch bar, running MacOS 10.13.