I've had the same thing happen to me with an HP printer. Moved the printer to another computer and the system would boot but wasn't able to find the printer to install it. I agree with eyeCpc about the Control Panel > Printers & Faxes, it is a related but separate issue. Most likely what has happened is that the printer has failed (Lexmark are notorios for dropping on a moments notice) and it took some of the windows system files with it when it dumped.
My suggestion, try to use the printer WiFi, and if it works, leave it be. Copy off any necessary files to CD/DVR/Online storage and do a clean windows install on the system. THEN, have your Mom get an in-case card reader and install it.
T.