56 means nothing! Go online (or anywhere you can get info) check out what's out there. Keep an open mind. For example all you considered where Microsoft products in your list. But for the last 10 years there have been more Java jobs than .Net jobs. I believe that's still true today (checked about month ago).
There are all kinds of ways to go. Consider the times and what you see as the future of programming. Have you considered writing mobile phone apps - very hot trend. I have a friend making a good living writing phone apps (he uses QT) all database related. He's currently replacing mobile terminals with phones - cool.
Have you considered using Python, Ruby (or many others) to get across platform? What about the fact that Apple is changing the landscape for desktops, laptops, and phones. Colleges sell two apples to one windows laptop. That's more than a trend - that's a movement. No MSdevelopement products on Apples.
Think the web is the way to go? Look at Air, Flex, Php, Python (lots of frameworks), simple Lamp, Ruby on Rails they all have major installs around the world. Web tools are getting very good.
Your age is not the issue. It's the fact you waited so long to start looking. On the other hand the fact you waited gives you a better handle on the what coming. Three years ago who knew Apple would be eating MS for lunch in the phone market.
Need money while you learn. Talk one of your customers into helping - upgrade them. You provide a discounted price and learn on their dime. Or go take a course or two.
Just do it!
John
John Fabiani
Woodland, CA