Apparently the board that you link does have a beta raspberry pi driver, so you may be good to go. It comes with a C program to demonstrate it. So, it should be possible to adapt that, and control it via GPIO, there may be examples of that in Magpi online magazine, otherwise there is this. You may want to mount the board or the RPI in a screened box (careful not to short anything of course!). Also, not close together, i.e. put them far apart inside the radio case that you have.
However, I think you may still need a good antenna for DAB too, but apparently it comes with an antenna to plug in so you may be ok. If it's no good, you may need to replace - if that occurs, post here and we can suggest what to do.
When you said "a new home where her FM radio isn't doing her any good", could you elaborate please? If there isn't much FM transmission, then I doubt DAB will be any good.
For Pi, as shabaz has said, the Pi driver for the MonkeyBoard is pretty easy to be used, however you will need to write your own display part to show the info, and adding buttons for the control. This method gives you the full control of what you want to do with the radio.
Alternatively, you could ask just to buy the module with MASTER firmware where the module will do the button, and LCD control. Fully like a kitchen radio. You just need to find a large I2C LCD for it, and connect large push button the the specific pins.
Hope this helps.
My nan is going blind and has moved to a new home where her FM radio isn't doing her any good.
She is a bit scared of technology so therefore has no internet connection and refuses to accept any form of tech
Initially I was looking at getting a DAB radio for here but I can't find one with a big enough screen or buttons so I was thinking...
Is there a way of intergrating a DAB radio USB device onto a RPi and control it via GPIO??
I have a vintage radio I've gutted which would hide the Pi nicely
The amp goes to the 3.5mm jack and GPIO buttons would intergrate nicely with the existing ones
I need help with the DAB reciever and software side
I found this from the googling I've been doing and don't know if it would be applicable but not much else
Esentially its this without the screen or internet connection:
Appreciate any help