The interfaces do suck. I can help out my mother, not because I'm smarter, but because I've learned to deal with the idiocy that's out there and understand some of the obtuse terms being used. I deal with crappy stuff all day long, she doesn't.
Most recent example: her email lost her address book and send buttons. Basically that toolbar vanished. Don't know how it happened, probably some obscure key sequence she hit by mistake. So I have to go to the menu (this being Thunderbird it hasn't yet removed menus in the asinine way that Firefox did), find the way to change the view, look at which toolbars are active, click on "message" in my guess that these buttons were on the message toolbar and not the mail toolbar. Not hard but completely obtuse to someone not versed in how UIs are done.
Next problem in the same phone call: it wasn't showing all her email. 15 unread messages that it didn't seem to display or download. This one had me stumped actually for a bit. Turns out she had accidentally clicked on one of the filtering buttons at the top of the list. It is not at all obvious what has happened, or what these buttons do. But click on one and it only shows messages that match its filter (she had clicked the one to show only messages from those in her address book). Now if there should be ANY menu bar that should have to option to be disabled, it is that completely optional one, not the one containing the button to let you send a message.
To really make this hard, Mozilla is changing their UI all the time, without warning, without consulting with users, with devs thinking they know what's best for the entire world. Leave the UI alone, and stop being actively hostile to the user.
Thankfully, I've got TeamViewer which makes remote control easy. I recommend it. You need the other end to have broadband though or it'd be too slow.