Since the stove is out of warranty, I told her she might be better off just looking in the yellow pages in the phone book and calling a local appliance repair place, because they'd probably be cheaper on a repair than Best Buy anyway.
She took my advice, settled on "A-1 Appliance Repair" here in town. The repair guy will be out Thursday between 1-3pm. Since mom has a doctor appointment tomorrow, that will work out fine.
This DOES beg the question however... WTF happened to Frigidaire?!? They USED to be a good company. But when a stove has a defect within a less than three year time span, something is seriously wrong! It's as bad as the Yamaha surround receiver I had recently that died three months after the 2-year warranty was over. Bought a Denon, it's been fine so far.