If you find that your Index window text is hard to read, you have the ability to change the text size. You can change the text size by clicking on the "pencil" icon in the upper-right corner of the Index window.
Once the icon is clicked, a new popup window will appear. Here you can select which type and size of font you prefer for the Label and Input Box.
Once changes have been made, click OK. You will need to close and then re-open the indexing window for changes to take effect.