I assume that you have found "Options > Theatre View > Items to show" and have been adding and removing stuff in there. You can do almost whatever you want to the menu structure, but you will lose a lot of functionality if you reduce the menu system to two or three items. Of course there will still be a lot of menu items at the top of the screen, once you select an item to show, such as "Movies". They are required items, without which MC isn't going to work.
In MC Theatre View, Escape+Escape will take you out of Theatre View to Standard View. If you can't change that behaviour, search the forum and Wiki for "Resource.xml" and "Custom Resources", then one you understand that capability, find the " <Entry Command="27000" Text="Escape" Param="27" />" line in the "Resource.xml" file and comment it out.
<!-- <Entry Command="27000" Text="Escape" Param="27" /> -->
That should stop the Escape key from working inside MC.
Then use the five keys Jim mentioned, plus the Backspace key on a keyboard, or the Back key on an MCE Remote Control, which I find invaluable in navigating MC.
Also, if you do use an MCE Remote, or can map its commands, when you get dropped out of Theatre View just press the "Guide" button on the remote. That will take you back into Theatre View onto the TV Guide page... if you haven't removed that already.
PS: If your wife's navigating is the main problem, create a menu in Theatre View just for her, with her two or three items, then just get her to always select her menu.
Thanks, some useful stuff in there, I had another go at it and got a working menu with just Movies, TV Shows and Home Video, that's a lot more comfortable to navigate. I also discovered that if you remove all but one of the subviews that avoids the getting locked in to the menus problem. I'd really like to remove the back, more, playing now menu but I that looks hard coded from what I found so far.
I had removed the TV Guide already ;-) we do have MythTV and TV Headend running but there doesn't seem to be a way to plug MC in to those so far. Not sure I want to replace TV Headend with MC on the Linux server, MythTV doesn't get used much any more. We don't really use a TV Guide anymore, TV Headend records all the prime time HD channels every day in a 6TB buffer and we pick out things we want to watch from the files there, we get ~6weeks worth.
I suspect that MC tagging will allow me to do something I can't do with all the other systems I tried, separate the TV recordings from ripped TV Shows and Movies but still have pretty metadata.
Wife's problem is when she has the remote from me, when I'm away she mostly stays in Netflix and Infuse on the Apple TV which is very clear and easy to navigate.
If Infuse was able to bitstream and had madvr image quality and HDR tonemapping I wouldn't have a HTPC. Infuse presents the media up front and you have to dig to get to settings, Theatre View seems the opposite approach, lots of menus and complex stuff up front and dig in for the media.
I used to manage a software development team and MC looks like a UI designed by a programming team for other programmers, Kodi has a bit of that going on too.
I'll have a big dig in Custom Resources, that sounds like the missing piece I hadn't found yet.
The exit menu would be IMO greatly improved if it landed you on the cancel item instead of the exit, a double press would keep you in Theatre View instead of dropped on the floor. Otherwise disabling the escape key might do the trick for now.
Thanks for the hints, I'm still at the stage where I don't know what it is that I don't know.