I'd say the best place for you to start would be here: "Hello World!" for Microsoft Windows (The Java™ Tutorials > Getting Started > The "Hello World!" Application)
That tutorial goes over everything you need to do to get "Hello World" working. There's a little bit of setup involved, but it goes into pretty good detail for beginners.
I would say that's your first step, and we can work with you from there to get you going.
As for the text size, you should be able to change that in your settings. Look in the control panel (start > settings > control panel) for accessibility settings. Or you could try simply decreasing your screen resolution.