Running Debian Testing with Gnome has been a joy. In my opinion the user experience is easier and better than that of Windows 7 or 8. Office staff could quite easily be trained to click on the Start key or the drop-down Activities menu or move the mouse to the top-left corner to start a program. Office software is quite good. Program-switching keyboard combinations are excellent. The Evolution mail client is very good. Browser software is the same as on Windows or a Mac. Problems with bad fonts, poorly designed UI, lacking drivers etc. are things of the past (with the notable exception of very new hardware).
This may not be possible due to the necessity of using specific proprietary programs that run only on Windows, for example. On the other hand, the level of tech support required is perhaps not significantly greater than what is necessary for installing and maintaining Windows on a bunch of machines.
On the plus side, everything is very fast, tasks like backing up files or systems are simple with GUI or terminal interface, and if you want to learn iptables and set up that router/firewall you can do that too. Everything you learn is an investment instead of an annoyance. Nobody is going through your company or personal files to serve you ads.
There's no reason any more, besides defaults and inertia, why Linux should have 2% desktop market share instead of 10% of somewhat technical people or even 20 or 30% of the general population.