Going against the crowd here .... I wouldn't recommend teaching.
Having seen the explanations you've given people here, I, too, am sure you would indeed be very good at teaching. But I'm guessing that you've had enough of all the stress of running your business. And teaching in schools can be horribly stressful, even if you're brilliant at the difficult discipline side of it, which I'm sure would also be the case for you.
It's not so much the teaching, which can be enjoyable if you have interested students. Apart from lesson preparation and the excruciating boredom of grading, there are deadlines and endless meetings after school, and aims and objectives, and WASC inspections which will take over your life for an entire year, and senior administrators sitting in on your classes so that they can tick boxes for the powers-that-be, to say that you're doing your job properly, even though they know that already, and midnight grading-period deadlines, after which the computer program locks you out and you have to crawl to the person in charge and grovel, case conferences and paperwork by the truck-load, and duties and parent conferences, and failing students who need extra help and make-up tests before or after school, and setting meaningful work by the end of today for independent study for the student who's going to his far-flung home country for six weeks, even though you haven't even finished preparing next week's lessons yet, and calls and emails to answer from parents who want you to give their child enough extra credit to make up for having done no work at all for the entire quarter, not because s/he is making no progress, but because s/he needs a B in order to play baseball next quarter, and replying to that email from the teacher across town who has an intern who wants to sit in on your lessons next Monday, and standing for an eternity blocking the door of the boys' restrooms while a student tries to get hold of a janitor because someone's thrown up on the floor of the boys' restroom after school, when before you can even think of going home you still have a pile of tests to grade, to try to fix that obsolete LCD projector that died inexplicably yet again in Period 8 today, and the principal's "Are we making the best use of our classroom technology?" survey to complete for tomorrow morning's meeting, and spirit wear to think up for next Friday's pyjama day, and food to find for the faculty's pot luck to celebrate xyz,.....and.....and....so on. And that lovely, hard-working and enthusiastic but weak little student was so excited to have made the freshman volleyball team today and you really ought to go and watch at least one game....
But some people thrive on it of course.
I just thought you should know! If you were in banking, maybe you're good at math and school districts tend to be desperate for math teachers, so if you'd like to teach, you might even be able to skip at least some of the accreditation hoops. And if you have a Master's maybe you could lecture in a college, instead.
Of course there are peripheral needs in education, too. Since you said you'd like to move servers, I gather that you're not totally tired of IT. Schools need IT support - increasingly nowadays, to be sure. They'd probably be overjoyed to have an applicant with your expertise to fill a vacancy in that field (and to stop the seventh graders circumventing the district's efforts to block youtube....)
I know you said you've had enough of having to market your business,do billing and so on. But if you just need some income, rather than a full-time job, have you ever considered setting up a small business as a trouble-shooter and tech help guru for private individuals with computer problems? I'm sure there's a market for that. As I'm sure you already know, use of computers by seniors is expanding dramatically, because they want, for example, to talk to far-away family members on Skype or Facetime. But because many of them are far away from their family members, they have no one to turn to for tech support. And it's really frustrating for them. This is the case for one of my own elderly relatives. I do what I can long-distance, but it would be SO much easier and quicker if someone could just sit next to her, show her multiple times how to do something if necessary and have her practice it until she was confident in doing it alone. I'd be thrilled if I could find a trustworthy computer guru locally, to help her. I think older people might trust and feel more relaxed working with someone close to their own age, who was patient, good at explaining (as you are) - and able to communicate using twentieth-century terminology! I don't think you'd need to do much marketing - after the first couple of clients, word-of-mouth would probably bring you all the clients you wanted.
Or maybe I'm too much of an optimist. I just want you to be able to stay "retired" from your old career if possible, so that you can enjoy retirement as much as I do!
[This message edited by Cally60 at 11:27 PM, February 21st (Friday)]