Tomorrow I'll be putting together a very similar build, but with an ASrock mobo, A3400 apu, non-ripjaw ram and slightly different case and psu. I've already done a different build with the Ranger case and Acer monitor. Ranger Case -- watch out for jagged edges in hidden spots. Install the hard drive before mounting the heat sink. It's a nice little case otherwise. Acer monitor -- the power light is too bright and blinks forever when the monitor is sleeping. Similar to a blue Christmas tree in the room... might even disturb your sleep if the computer is in the bedroom. Otherwise a nice monitor for the price.
Watched and read a number of reviews on the APU and people are mostly pleased with the performance within its limitations. I think your mother will be happy with her new computer. I'm looking forward to mine being used for general family fun, net surfing and Home Theater. I'll also be using Linux (Pinguy + XBMC).