the mini is a harrowing experience the first time, but it's by no means hard to pop open. It just involves a putty knife.
The putty knife goes in bottom of the machine along hte seam at the front, bend it slightly to unhook the latches, and separate. Some walk-throughs I found (even in video form) have you jamming that thing into the sides as well. It's completely unnecessary to do so.
Then it's just four tiny screws, unplugging the fan controller cable, and disconnecting the ATA cable from the optical drive.
Is it enjoyable? Certainly not. But we need to keep in mind the needs of elmopuddy's wife. OS X is lighter on RAM usage than Vista - even Leopard. 1GB is good for light work, 2GB is better. 4GB is unnecessary for her workload. The stock 60-80GB drive is also usually plenty, depending on what you're doing. So if you can find a Mini with 2GB, you don't have a need to open it.