I would recommend creating a custom XP install disc using nLite. With nLite you can pick and choose which components of Windows you want to be installed. You can also add patches, service packs, drivers, accessibility options, and custom programs to be included in the DVD like Firefox and AVG.
This is what I've done for my grandmother. After creating a disk that comes with all the software she'll need, all the drivers, I've got a restore disk that I can just throw in the drive if it ever needs a reformat, and it's an unattended install.
I keep a copy of the nLite image I used for her on my local machine, so for this christmas, I'll load it back up with some updated patches, and throw it in her DVD drive when I get there (after backing her bookmarks up on a USB drive of course).
nLite has a learning curve, but it is small. I would recommend trying a VPC install once or twice before getting your disc "set".