I think this isn't even an issue since she's able to use Vista and Apple products quite well 
with MacBook - it's able to read photos and document files from PC but about database thing... I'm not quite sure about that. Do you know exactly what kind of file? Access?
god bless him
Toshiba is great too. and reliable.
Not a problem. Any laptop (PC/MAC) can connect to keyboard/mouse via USB/Bluetooth/etc.
based on what you said in previous thread... she uses iPad/iPod for everything and PC for AOL... sounds like she's not gonna touch it for a long time.
she can simply burn them to DVD and store it in USB Thumbdrive and dropbox.com (all 3 for redundancy reason). That way - she can come back to it anytime she wants.
If she has no problem with that - then she should be fine with HP netbook but screen size might be a big issue so just about any cheap HP notebook should be fine. I'd prefer Toshiba but HP is fine.