What is the ideal height of a button in regular desktop applications?

On most GUI creator (I just checked Qt Creator and Flex Builder), it seems the default button height is about 22 pixels. This is what I use for most desktop applications I create except those I make for myself. In this case, I use bigger buttons - 30 or 40 pixels height because I feel that, with 22 pixels, I need to "take aim" more than necessary. Also, as our screens get bigger, I think we can make buttons bigger too.

So are these 22 pixels based on some proper usability study? Or is it an arbitrary number that perhaps comes from an old default in Visual C++ or some other popular development environment? If 22 is not a good default, what button height is generally recommended? Any suggestion?

(By the way, I'm only talking about regular desktop applications)