That's so hard because I like them both. I wouldn't mind having either of these breeds. Five years ago, I would have said Beagle, hands-down. They're one of the cutest breeds and friendly, too. Since then, I've known 2 mini schnauzers who were great little dogs, and easy to train, so.......
I think for my situation right now with very little open area to run, I'd go with the Schnauzer. However, I really prefer a Beagle.