Hi Julie
I know this is only my experience, but 2 years ago we bought a 42 inch plasma TV. We didn't like it cos it was too big to watch the screen without having to follow the screen about with your eyes (like in the cinema) if that makes sense... We also found the picture looked a little pixelated. Unfortunately (or fortunately..?) it broke after 4 months and couldn't be repaired so we swapped for a 36 inch LCD which we are very pleased with.
I'm sure others may prefer plasma, but just thought id share my thoughts.
PS Well done to your Mum too