Don't understand why you cannot take your SanDisk SDDR-09 with you in the move from OS 9 to OS X.
It's a USB device that needs no drivers under OS X and is just a simple plug and play(really!) device. Plug it into your G5, put in a card and watch it mount on the desktop. If you have iPhoto set up right, the card will also launch iPhoto when mounted. The above instructions, except for the mounting on the desktop and the iphoto bit, also apply to your wife's XP machine.
We use a SanDisk disk reader at work and it moves around the building connecting to all sorts of different OS's

Try it

P