Just thought I'd mention
Powermax, haven't been on the site for quite a while, but they seemed to have a whole lot of used Macs.
Nobody else mentioned it, but wouldn't cleaning up the desktop (emptying, actually)
vastly improve performance? Also, checking her log-in items, etc. I'm sure if you googled "ways to speed up your mac" or similar search, you may be able to find some things to easily do that speed her existing mb up. You could download Onyx & spend a couple of hours doing some maintenance/cleanup with that (Spending time with Mom... PRICELESS!).
Maybe somebody else is better able to tell you how to set up her desktop to stop everything being saved there, seems like I've read about this, I know saving right to desktop is not ideal. I avoid saving anything onto mine, only 3 items on it at the moment, just something I got in the habit of, so I'm not really familiar with how to set it up with easy access to all her stuff while still taking a load off the computers resources.
I'm 63! Jeez, I must be about ready for the scrap heap myself by the sound of some of the replies here, hopefully I can get my new 500Gb EVO installed in my mbp before I go completely senile
