Pretty much anything by Brother. They encourage self-service, have super cheap consumables, are very efficient, and have some of the best plug and play experience around.
Oh yeah, my mom has been running a fax/inkjet printer from Brother for a good part of a decade. Ink is super cheap, and it works really well. Only downside is that printer isn't networked.
I ended up getting her a used network printer before those dongles existed. She's just stubborn with what she will use. Honestly, I might just buy her a replacement laser printer and toss out all the old ones at some point. She finally admitted not needing a fax anymore a couple years back.