Is there a way to change font and/or font size?
Otherwise this software would be inaccessible and worthless for us (as a Company)! :-S
We're very sorry to hear that :-(
Unfortunately, it's not possible to change the font size of the Windows app itself, though if you're asking due to the use of a display with high pixel density - we're working on adding support for such displays.
Please note that you can also use Todoist on the web in any browser and each browser will allow you to zoom in on it with Ctrl+ and zoom out with Ctrl-
A Windows 8 Metro App would be a welcome addition