Actually, I have gotten a similar call from the bank recently. Except that they called to confirm the last five transactions. They did not ask for any personal information. The transactions were read to me. Oh, and when they called, it was just a message with a number to call back, which when I looked it up, belonged to the bank.

But yes, if they ask for any personal information, except perhaps for name to see if you are registered to the account, it is a scam.

What about, "Ok, mom, go to ipchicken.com and tell me what it says right under Current IP Address" followed by ssh'ing into her computer and editing the conf file?