Clarity - 76593 P300 Amplified Corded Photo Phone - White

Yes you can program the phone so all she will have to do is press the picture and it calls the number you have programed. The red light does light up when the phone is ringing. My mom is 94 and loves it. with her old phone she couldn't hear anyone and now she hears everything!!!!! I would buy it again without hesitation.

Right.

Pictures are roughly 1 square inch. I printed family pictures to size.

Yes the volume of the ring can be adjusted. The adjustment of the volume of the ring is separate from the volume of the caller's voice.

This corded phone is hearing aid compatible (mild to moderate hearing loss), so it could help your mother, but it really depends on her specific level of hearing loss. I have included a few other corded phones that could potentially help her hear the conversations better. Thank you!