I have an old 700c MTB from before they were called 29ers. It's a rigid framed bike and I think it's great for commuting, especially in the winter since there's a lot of options for studded tires in the 700c size.

I don't know if there's anything that will fit somebody whose 5'2 without compromising the geometry. Maybe. Even with road bikes you'll see 26" or 650 (b or c, I get confused) wheels on the smaller frames.