AFAIK OS X.

She just needs to run apps that won't run in Classic. I gave her my PB 170 (the one I have now), but after a while, I decided that I really want it back, and she could appreciate the PB 1400cs more, since the 170 still has several viruses (nVIR A, MDEF, other crap) that have proved a pain in the rear end to remove due to clogging the desktop file almost immediately.