Wordpad text mode defaults to Courier 10 which I end up using a lot, but if I want something "readable" I'll change it to Times New Roman 12 or 14, so it looks more like a page from a book. They spend centuries figuring out fonts for easy reading, and the old "standards" are still in common use, so they work for me. Every once in a while text actually needs to be monospaced, so then it's back to Courier.
ETA: And why use Wordpad instead of Microsoft Word or OpenOffice's word processor? Wordpad does 95 percent of what I ever want to do for 95 percent of the times I write, and it loads in half a second vs. ten seconds or howeverlong for a "REAL" word processor, and also runs faster. I prefer faster response rather than being too feature-laden with stuff I rarely use.
I write movie scripts, so I am obligated no matter what my preferences to use nothing else but Courier New, 12-point, 10-pitch.
I can understand there might be a submission format, but do you really have to WRITE in the same format as your submission? Modern word processors allow you to change things after they are written, you know...