Not via user settings, no.
You may however override the fonts.xml file to change the fonts size, or even the fonts in use.
To do this, create a skin override folder in %AppData%\SecondLife\ (in you case, and seeing your log, this would translate to C:\Users\Owner\AppData\Roaming\SecondLife\). In this folder create a "skins" sub-folder, then in the latter, a "default" sub-folder, then in the latter again a "xui" sub-folder, and finally in the latter a last "en-us" sub-folder. You would then have an empty %AppData%\SecondLife\skins\default\xui\en-us\ folder (C:\Users\Owner\AppData\Roaming\SecondLife\skins\default\xui\en-us\ in your case) where you can copy the fonts.xml file found in the skins\default\xui\en-us\ sub-folder of the installed viewer.
Once you have your override fonts.xml file, edit it with a text editor (not a word processor), and change the parameters you wish. The UI fonts in use are found under "SansSerif" and "SansSerifBold" (MtBkLfRg.ttf and MtBdLfRg.ttf respectively), and you could change their associated file names by other fonts file names of fonts distributed with the viewer (e.g. Roboto or DejaVu ones: see in the fonts\ sub-folder of the installed viewer for the exact file names), or with fonts present on your system (see the file names found by the viewer, which are listed in the log file in the "LLFontRegistry::dump: file: somename.ttf" lines). You would also likely have to adjust the font sizes ("Small" and "Medium" for UI fonts), at the end of the fonts.xml file, to make them fit in the UI...
If the problem is with too high a screen DPI which causes the UI to appear "too small", then you could instead use the UI scaling slider, in the "Preferences" menu, "General" tab: move the "UI size" slider slightly to the right, then "Apply", rinse and repeat until satisfied.
Please, do not post logs as plain text: instead zip them and post them as an attachment (I removed the second part of the log, which was irrelevant anyway, since the interesting info about your system and the fonts can be found at the start of the log).