I got up enough courage to go on. My biggest worry would be Windows corruption, where people depended on the pitiful performance. As well, there is the issue with laptops, where every important person takes theirs home to have the kids play with it. Or they go on trips and do everything wrong.
We start with the assumption that we have enough money, and the family owners aren't being cheap. In fact, I would want to go in after a big failure, and people are clamouring to move up from XP. All these companies run win7 or xp, and the move to win10 would be just as severe.
My big push would be to go to Google Apps with Chromebooks, and put in some heavy servers to handle legacy win applications. I suspect there would be some pretty horrible ones. I would assume that all existing win machines are owned (pawned, intruded), and cross-over day would be fun. I would only allow contact with the win servers through a filtering proxy server. Everything internal would be encrypted and 2 factor.
For internal communication I would go to Slack, you need some heavy contact between sales and product development. Naturally, all of these would allow some excellent contact with the outside world through top-notch web development.
I would contract everything out, since I want to leave. This could be taken over by a young person without too much risk. :) I would also include internal mouse traps, such as files labelled "Celebrity Nude Shots".
**The old company had massive IT corruption, first the mainframes, then windows. IT dept. became outsourced, and its life depended on picking the most miserable system that required the most servers, and the most labour to keep running. They were very good at it. :)